Smithsonian.com

The deathstalker scorpion, a Middle East native shown here in captivity, kills several people each year and occasionally hammers its stinger into the hands of hobbyist collectors. Photo courtesy of Flickr user Furryscaly.

Give me a rainstorm in the night, a herd of pigs trampling past, even a bear—but if I’m camping without a tent, spare me the bugs. Because it’s the little things in the woods that creep many of us out the most, and the thing is, not all of them are so little—and worse, some have fangs and a hundred legs. Centipedes that can overpower a snake, spiders a foot wide, rodent-sized scorpions and other creepy crawlers of the forest floor offer good reason to sleep inside a tent. For years, I only camped under the open skies. If it rained, I would wrap up in a tarp or sleep under the awning of a church. But one night in Portugal while reading a book by the light of my headlamp, a huge spider with legs like an imperial walker came dancing onto my tarp and into my lap like a mad dervish. I screamed, panicked, flew home and bought a one-person, three-pound backpacking tent. That doesn’t mean I always use it, but here are a few good reasons why I should:

Deathstalker scorpion (Leiurus quinquestriatus). The deathstalker scorpion just might have the coolest name in the animal kingdom. A Middle East native, it grows to four inches or more in length, brandishes a horrifying pair of pincers and lives up to its name. Often described as “very aggressive,” it hammers its stinger into many people every year, killing several. Most victims, though, just suffer extreme pain in the region of the bite, along with drowsiness, fatigue, splitting headaches and joint pain, with symptoms sometimes persisting for months. Meanwhile, most scorpions are less dangerous than simply creepy. David Quammen—an admitted arachnophobe—elaborates on this in his essay See no Evil, published in his 1988 collection The Flight of the Iguana. He writes, “…scorpions are perhaps the most drastically, irredeemably repulsive group of animals on the face of the Earth, even including toy poodles.” Tent, please.

Goliath bird-eating spider (Theraphosa blondi). The biggest of the tarantulas and the world’s largest arachnid, the Goliath bird-eating spider lives in the rainforests of South America. Its legs can span the width of a dinner plate (should it find its way into your kitchen cupboard) and it’s large enough that it can, with ease, kill and eat mice—not to mention birds. The animal’s fangs may be an inch long, and yes, they will inject venom. However, the bite of a Goliath bird-eater is hardly worse than a bee sting to a human—but for campers, do you really think that matters? No way. This beast is among the nastiest things that could skitter across your face in the dark night of the Amazon. Zip up your tent.

Giant desert centipede (Scolopendra heros). On a hot afternoon in September 2003, I was bushwhacking out of the mountains in the Baja California desert not far from La Paz. I fought and kicked my way through the thorns, ducking through tunnels in the brush, and finally made it to the quiet shore of the Sea of Cortez. I plopped down in the sand, my back against against a rock, opened my backpack, and went digging for my mask and snorkel—and then appeared the ugliest monster I’ve ever seen: a seven-inch centipede that came snaking out of the pack, right past my arms and on a trajectory for my face. It was, I’m almost sure, Scolopendra heros. I screamed in a howling panic, leaped from the sand, and went backpedaling into the water, where I fell on my butt and and watched the centipede vanish into a rockpile. This creature, I later was told, is poisonous and can, if it feels especially wicked, bite and deliver venom with its fangs as well as some of its legs. And you want a much, much nastier story? In a documented case in Arizona, a man put a garden hose to his mouth and turned on the faucet to have a drink—and can you guess who came charging out of the nozzle? S. heros scuttled right into his mouth and bit his tongue, leaving him in pain for days.

This giant desert centipede has overpowered and killed a lizard. A tent may block your view of a meteor shower, but it'll keep monsters like this from scuttling into your sleeping bag. Photo courtesy of Cabeza Prieta Natural History Association.

Bullet ant (Paraponera clavata). An inch long and known to jump from trees upon its victims, the bullet ant of Central and South America delivers what is said to be the most painful sting of any arthropod. It hurts like a bullet wound, people say, and the pain may persist for 24 hours. In the ant’s defense, Paraponera clavata is not aggressive unless bothered—so if you get stung, you must have asked for it. The ants also offer fair warning before attacking, emitting a musky odor and an audible “shriek.” If you detect anything of the sort while hiking in the Amazon, turn and run—or just suck it up and experience this phenomenal bite like a man,which is exactly what teenage boys in certain forest cultures do to prove their manhood. Anyway, the bullet ant’s bite rarely kills. 

Brazilian wandering spider (Phoneutria fera). Widely considered the most poisonous spider in the world, wandering spiders reportedly hospitalized about 7,000 people in Brazil alone between 1970 and 1980 and may have killed more people than any other arachnid in the world. Phoneutria fera is often regarded as the main offending species, but others of the same genus, including the Brazilian huntsman, have similarly toxic venom. The spiders are known to wander and explore, often hiding in clumps of bananas, and often entering homes to have a nap in the toes of a shoe by the doorstep or a vacant pant leg in the clean laundry pile—and surely a cozy sleeping bag would be a fine dwelling site for a wandering spider. Symptoms of a bite include pain, redness and immobility in the area of the bite. Paralysis and death by asphyxiation may follow. In survivors, tissue affected by the poison may die and rot away. Another bizarre symptom immediately following a bite in men is a painful erection lasting hours and sometimes causing impotence.

Mosquito (Family Culicidae). Consisting of 41 genera and more than 3,500 species in the family Culicidae, mosquitoes may not inspire nightmares or make our skin crawl the way that arachnids can, but what other element of nature so frequently ruins a night of camping? Whether on the boggy tundra, in the blazing desert or in the swamp country, mosquitoes may swarm us in clouds. Even a bona fide house with walls and a roof can’t always protect against mosquitoes, and in parts of the world people sleep with permanent netting over their beds. These insects insect may be the most dangerous, too: in 2003, malaria killed 3 million people—infected thanks to mosquitoes. And these bloodsucking disease vectors dealt me what was one of the most torturous nights of my life while camping (with no tent) on the shore of a mangrove lagoon in Mexico. After about 500 bites, I went stumbling into the village around midnight and pleaded with a bartender for bug spray. He said citrus juice was the most potent mosquito repellent—trick from his grandmother—and he threw a lime at me from his cocktail making tray. It didn’t work. After bite 2,000 or thereabouts I wrapped a towel around my head, jumped in the water and breathed through a snorkel until dawn brought relief.

The handsome face of the bullet ant, a New World jungle native whose bite may be the most painful of any arthropod on Earth. Photo courtesy of Flickr user EOL Learning and Education Group.

A farmer in the Congo harvests jackfruit, the largest tree fruit in the world. Photo courtesy of Flickr user Scamperdale.

In faraway lands, a walk through the village street market is a sure bet for zeroing in on the best of a region’s edible fruits. And in spite of museums, adrenaline sports, helicopter tours, golf courses and all the other offerings cut out and polished for commercial tourism, I’ve often found the local bazaars and farmers markets to be the most exciting of exotic cultural experiences. New sights, smells and tastes meet you at each visit, and as you near the equator, the diversity of available local edibles increases until you may discover new fruits at every market stall. Watch for mamey sapotes in Cuba, blackberry jam fruits in Brazil, peanut butter fruits in Columbia, the lucuma in Peru, Sycamore figs in Yemen, mangosteens in Thailand—and that’s just the beginning of the long, long list. Following are a few suggestions, continuing from last week, of fruits (and one fruit wine) worth a journey to see and taste.

Jackfruit, South Asia. When a falling apple bonked the brain of Isaac Newton, the theory of gravity is said to have been born. But falling jackfruit can kill. This huge fruit, kin to the dainty mulberry, can weigh more than 100 pounds. Should you find yourself in the tropics on a sweltering day, hang your hammock in the shade of a guava tree, by all means—but beware of the jackfruit. The trees are common as cows in much of South Asia, and the oblong, green fruits are covered with a thick reptilian hide that exudes a sticky latex-like sap. Knives and hands should be greased with cooking oil before butchering a jackfruit. Inside are the edible parts—yellow rubbery arils that taste of banana, pineapple and bubblegum. The fruit is loved by millions, though the wood of the tree has value, and in Sri Lanka more than 11,000 acres of jackfruit trees are grown for lumber. The species occurs throughout the tropics today. In Brazil, where it was introduced in the late 1700s, it has become a favorite fruit as well as a problematic invasive species. Asian communities elsewhere around the world import jackfruits, many of which are grown in Mexico.

White Sapote, Mexico. A green-skinned apple lookalike with creamy, white flesh as juicy as a peach and as gratifying as a banana, the white sapote may be one of the most outstanding tree fruits in the New World. Though native to Mexico and Central America, it can be grown in temperate regions—as far north, even, as the foggy San Francisco Bay Area. I first met this fruit while cycling through Malibu, California, when I discovered hundreds of apple-sized orbs spilling from a pair of trees outside a driveway along Highway 1. I picked one up, found the fruit as soft and pliable as an avocado, and couldn’t resist taking a bite. I was stunned by the flavor and equally surprised that I had never seen this creature before, and I crawled into the culvert to salvage the fallen beauties. I packed about 20 pounds of bruised and oozing white sapotes into my saddlebags and, with a heavy heart, left perhaps 100 pounds more to spoil. That was in October 2004, and I suppose that the trees are still there. (If you go, harvest only the fallen fruit.) Just months later, I was walking through the desert mountains north of Cabo San Lucas on a dirt road that crosses the Baja Peninsula from El Pescadero on the Pacific coast eastward before the road connects with the main highway. Just before that intersection, I met a local ranch family who told me that in a nearby canyon was a semi-wild white sapote orchard. They spoke reverently of the trees and their fruit—but said I had just missed the season.

Fig, Greece and Turkey. A perfectly ripened fresh fig is soft and sweet as jam, making this Old World native essentially unable to withstand the rigors of long-distance travel or long-term storage. In effect, the fig is one of the very last fruits that is mostly unavailable outside the season and place where it is grown. Although Spanish missionaries tenderly packed fig cuttings with their guns and cannons and planted the lucrative food source throughout the New World, and although British explorers introduced the fig to the Pacific Islands and Australia, nowhere in the world do figs occur in such abundance as along the coast of the Mediterranean Sea. Portugal to Israel, Egypt to Morocco, and throughout the region’s islands, fig trees grow like weeds. Ravenous goats, worthless rock soils and never-ending drought, all in combination, cannot stop the miraculous fig, and the trees take over abandoned villages. They bust apart the cobblestones of bridges and castles, and they drop their fruits upon the world below. Esteemed cultivars grow in gardens and dangle over village fences. Wild seedlings and forgotten heirlooms grow in vacant lots and abandoned groves. In high season—August to October—sidewalks vanish as falling fruit accumulates like jam on the ground. Picking sacks full of figs is a sure bet in nearly every village below 3,000 feet. Greece and coastal Turkey are ground zero, but hundreds of varieties and millions of trees grow in Spain, Croatia, Italy, Portugal, France and Georgia—nearly anywhere in the region. Want to skip the high season and still get your fig kick? Then go to the island of Cyprus, where several local varieties ripen as late as December. Can’t travel until February? April? June? On parts of the Big Island of Hawaii, fig trees produce fruit year round.

Throughout the Mediterranean and Middle East, village sidewalks disappear under splattered fruit during the height of fig season. This scene was photographed by the author in southern Turkey in late September 2010.

Pawpaw, Appalachia. This is one fruit you may not find in your average farmers market. It’s been nicknamed “poor man’s banana” and described as “America’s forgotten fruit”—but why and how did we ever forget the pawpaw? It’s got the fetching qualities (as well as the DNA) of a tropical fruit, but this cold-tolerant species is as American as the Great Lakes, the swamps of Florida and the backwoods of the Appalachians. Abundant in places, it even occurs naturally in southern Ontario. Lewis and Clark encountered this relative of the cherimoya and were pleased by its creamy, custard-like flesh, and many people in the Eastern states are familiar with the pawpaw fruit, which may weigh five pounds and is the largest native edible fruit in America. On the shores of the Potomac River, pawpaw trees grow wild. Indeed, foraging may be the only way to taste this oddity. For whatever reason, pawpaws are scarcely cultivated and even more rarely sold in markets. So pack a machete and a fruit bowl and get thee to Kentucky. Take note: Kiwis call papayas pawpaws. That is, the “pawpaws” you see in New Zealand supermarkets are simply mislabeled papayas.

Cashew wine, Belize. I first described this specialty product of Belize two weeks ago. Cashew wine is not currently imported into or sold in the United States (or if it is, I haven’t heard about it) and short of having a friend pack a few bottles home on their next trek to Central America there may be no way other way than visiting Belize to have a taste (well, you can order it online, but that’s no fun). But it so happens that I was lucky enough to sample a bottle kindly sent to me last week by Travellers Liquors, the Belize-based maker of Mr. P’s Genuine Cashew Wine. Made from the fleshy cashew apple, Mr. P’s is tawny colored, like whiskey, on the sweet side and very aromatic. It smells and tastes like a lively stew of sour pineapple, molasses and maple syrup, with a strange and elusive hint of WD40—an exciting change of pace from the fermented juice of the grape. And here’s a morsel of jungle lore: Belizeans told me in 2002, as I traveled there for a month, that cashew wine will make a person drunk twice—once while drinking it, and again the next day if you should fall asleep in the sun.

I’ve surely missed a thousand other good fruits. More suggestions,  anyone?

The Great Blue Hole of Belize was named by Jacques Cousteau as one of the world's top diving sites. Photo courtesy of Flickr user DrJohnBullas.

I am not a SCUBA-certified diver and I may never be. Instead, I free dive and have been for about 13 years, mostly along the coast of California, and I have no interest in introducing tanks, tubes and pressure valves to the simple relationship I have with the water. I can only imagine the burden of swimming with all the mechanical gadgetry and gear on my back that tank divers must wear, or the logistical nuisance of having to fill the tanks prior to each dive. Free divers must fill only their lungs, and sometimes just 5 or 10 feet beneath the surface we find all that we might ever hope to: the mangrove thickets of Belize, alive with nurse sharks, reef fishes and even crocodiles, or the kelp beds of California, where many divers spoiled by tropical reefs may be born again as they discover this unmatched habitat. But SCUBA technology grants access to a deeper world that I, again, can only imagine. And I think that the magic of SCUBA diving can be simmered down to one flat and obvious fact which an old friend and diving buddy once illuminated for me as we debated the pros and cons of air tanks:

“Dude,” he said. “You can breathe—underwater!”

There’s no arguing with that. And so we go, tanks and tubes and valves flowing with pressurized air, into the finest SCUBA diving destinations in the world.

Great Blue Hole, Belize. Jacques Cousteau visited this site in 1971 and declared the Great Blue Hole of Ambergris Caye to be among the best diving locations in the world. The Great Blue Hole is a wonder of geology, a 410-foot deep sinkhole located within the Belize Barrier Reef system and was created through forces similar to those responsible for the underwater caves of the nearby Yucatan Peninsula. The Hole is more than twice as wide as it is deep, making it less like a bottomless pit than a huge pothole, yet the vertiginous void may offer divers something of the feeling of facing off with the edge of the world. Descending into the hole, one will encounter local residents like groupers, various sharks, great barracuda and a diversity of other species. Bottom topography consists of sand, reef, many varieties or coral and ancient limestone stalactites, as well as caves and dramatic outcroppings that look like cathedrals. Visibility may exceed 150 feet and surface water temperatures rarely dip below 80 degrees Fahrenheit.

Wrecks off Papua New Guinea. Things under the sea may be categorized into two classes: naturally occurring or the far less common anthropogenic. And that’s where diving can get creepy—coming across tools and devices and vehicles, objects that weren’t supposed to end up here but which, through some mishap or disaster up above, sank into watery graves. The sea floor is littered with manmade stuff, and few underwater adventures may be more thrilling than exploring a wreck. World War II was an era in which Davy Jones acquired a wealth of collectibles for his locker, and a great many planes and ships went down around Papua New Guinea. The Boeing Blackjack B-17 bomber is just one of the region’s popular dive wreck dives, sporting a very recognizable cockpit and turret guns. Discussing the “best” wrecks seems a bit callous, considering that many people have died on them. Some wrecks, though, are sunk intentionally, without casualties, as tourist draws and habitat enhancers, such as Papua New Guinea’s Pacific Gas, which has rested in 145 feet of water off of Port Moresby since 1996. On the wrecks where human lives may have ended, dive with respect.

On the Thistlegorm wreck in the northern Red Sea, divers find intact cargo from the World War II era. Photo courtesy of Flickr user mattk1979.

Red Sea, Egypt. Surrounded by land, the Red Sea experiences a temperature range much like that of a continental lake, with waters in January as cold as 65 degrees Fahrenheit and, in the late summer, as warm as the high 80s. Furthering the flux in temperatures is the north-south extent of the Red Sea, which crosses almost 15 degrees of latitude, from 30 degrees north into the tropics, where its waters touch the coasts of Eritrea and Yemen. The Red Sea wreck of the Thistlegorm, a British vessel sunk in 1941 during an air strike, is said by some to be the “best” shipwreck anywhere, with motorbikes, guns and vehicles still intact and viewable. In the realm of living things, whale sharks occur here in some abundance, and they’re just the biggest of the 1,100 fishes to be encountered in the Red Sea. About 200 of these species occur nowhere else. Marine mammals include the sluggish, vegetarian dugong, which grazes on sea grasses in the shallows and in lagoons. Further from shore, the sea floor plunges to some 10,000 feet deep. In many ways, the Red Sea is much like the equally splendid Sea of Cortez in Mexico—a sea also two miles deep, also a product of tectonic activity, also ranging from tropical to temperate, also of giant temperature range, also surrounded by desert and date palms, and also one of the most beautiful places in our mostly salt-watery world.

Great Barrier Reef, Australia. The most renowned diving location, the Great Barrier Reef is also the biggest barrier reef and, like nearly any tropical reef, a hotbed of colorful coral snags and zillions of striped fish darting in and out of the cracks and, well, you know—all the same stuff you’ll see in the travel brochures and computer screensavers. We could, I’m sure, go on all day about warm-water reefs—of Bermuda, Thailand, Micronesia, the Caribbean, the Mediterranean. Those and others like them are the places that most “best diving” lists consist of, and the Great Barrier Reef, like them, deserves every medal it wears around its neck. But what more is there to say by now about clownfish and big friendly grouper and how clear the water is?

Monterey Bay, California. And so I come home, to the waters of the American West Coast. They’re often murkier, surgier, spookier and gloomier than the seemingly airbrushed beauty of the tropics—but I’m just one diver of many who first fell in love with the world underwater in the stately kelp forests of the California coast. Those of Monterey Bay might be the most famous, teeming as they are with rockfish and surfperch in the water column, lingcod on the bottom, abalone in the rocks and, backstroking over the kelp fronds on top, sea otters. The average “vis” in places—such as Point Lobos State Natural Reserve, just south of Carmel—is 30 to 40 feet but can be as much as 60 on the best of autumn days. A jaded SCUBA jock who lives in a thatched beach hut in the Maldives might spit on such conditions and go back to bed, but for temperate-zone divers, even just 25 feet is like magic. The waters off Northern California, too, are frigid. Go in without a hood here, and it’s an instant head-freeze so shocking that you might almost pass out. Many divers even wear drysuits, though most can pull off several hours in the water with a 7-millimeter wetsuit. But for the beauty below sea level here, it’s worth braving the elements—the towering trees of kelp, the shafts of sunlight slicing through the canopy, the schools of fish silhouetted against the gloomy blue. Kelp forests grow all along the West Coast, Alaska to Baja, as well as around the world, from New Zealand to Chile to Japan to Scotland. Almost anywhere, in fact, where water touches shore is worth a dive—with or without air tanks on your back.

There are no clownfish or coral fans or gentle reef sharks here, yet the kelp forests of the California coast provide underwater scenery that no tropical reef can quite equal. Photo courtesy of Flickr user Diving_Mullah.

The author and his bike stand about 850 feet above San Francisco on Conzelman Road. Repeated 10 times, this little hill amounts to a world classic of climbing.

On St. Patrick’s Day, my brother and I rode our bicycles to the top of Conzelman Road in Marin County, and from the overlook above San Francisco, with a view of the Golden Gate Bride, we drank a strong ale from our local Lagunitas Brewing Company. A man, just out of his car and camera in hand, said, “You guys earned your beer, eh? Makes me feel lazy.” We nodded but didn’t have the heart to tell him that we’d actually pedaled to the top, gone back to the bottom, and repeated the mountain ride nine more times. The four-hour stunt was our birthday gift to ourselves (we’re twins)—a 35-mile ride in which we gained more than 7,000 vertical feet. Not bad, but at the end, we were dizzy with the numbing repetition of the feat, and we knew one thing for certain:

“We need a bigger hill, Andrew,” I said to my brother.

Because for hill climbers like us, long, steady, unyielding climbs are the holy grail of athletic conquests. Climbing such roads on a bicycle delivers endorphins to the brain, strengthens muscles and calms the mind. It works like yoga, asking concentration while allowing meditation. Big climbs mean health, nourishment and prolonged youth. We thrive on them, and hill climbers like us can’t help but measure the worth of a landscape by its rise over run. And so we scorn Holland and its tidy flat bike paths, and we dream of mountains and those rare roads that go upward for thousands upon thousands of feet without pause. But where are these monsters—and how high do they climb? The following list includes just a few of the best uphill bike rides in the world. You needn’t be a hill climber to love them, because they’re equally thrilling to ride down. Just check your brakes and wear your helmet.

Haleakala, Hawaii. Rise Over Run: 10,023 feet of climbing in 35.5 miles. The road up the Haleakala volcano delivers one of the longest highway ascents, with the most vertical gain in one push, in the world. It is also one of the most downright difficult rides, as there is virtually no flat or downhill ground once the climbing starts. Moreover, the air grows thin with the altitude, heightening the difficulty as cyclists struggle to catch their breath. Not surprisingly, some tourists come to this mountain for only the thrill of going down it. Maui Easy Riders, for one, offers what is billed as one of the longest guided downhill bike rides in the world.

Khardung La, India. Rise Over Run. 5,566 feet in 24 miles. Elevation measurements seem to vary in the Himalaya depending on the source, the country, the website and the altimeter, but still, cyclists agree: Khardung La out-passes nearly every other highway pass in the world. It offers only half the vertical gain of Haleakala, but it leads cyclists to unsurpassed heights of more than 18,000 feet above the sea. Supposedly, no “motorable” road goes higher than the one to Khardung La. Before going down, bundle up against the chill.

Mont Ventoux, France. Rise Over Run: 5,303 feet in 13.6 miles. Three roads lead up this famed climb on the western edge of the Alps. Each is tough, but the steepest is considered one of the most challenging bike rides anywhere. The climb has gained notoriety as a recurring feature in the Tour de France, often as a dramatic mountaintop stage finish, with all cyclists sprinting for the summit on the steep home stretch. But during the 1967 Tour, Mont Ventoux reminded cyclists that hill climbing is not all fun and games. Legendary British cyclist Tom Simpson died on the way up due to heat exhaustion, dehydration and, possibly, a combination of drug and alcohol use. Romantics may prefer to believe it was simply the mountain that took his life.

A cyclist fights gravity and grade on the final miles to the top of Mont Ventoux, one of the most legendary cycling climbs in the French Alps. Photo courtesy of Flickr user The Pingus.

Sualmaz Pass, Turkey. Rise Over Run: 5,540 feet in approximately 25 miles. This climb from the Mediterranean Sea into the Toros Mountains does not make the lists of the world’s great rides, nor is its statistical info posted on any online cycling forums, nor do teams of Lycra-clad road bikers blitz up and down it on warm weekends. I know of the Sualmaz Pass only because I know the pass personally, and it’s got all the charisma of a world classic. It begins in the town of Anamur, roughly at sea level, among groves of banana trees and subtropical sun. Then, inland several miles, the ascent begins. The lush valley floor drops as the mountains soar overhead. Bring food and water (I ran out of both when I climbed it in 2010) and start early (I got a late start and arrived in the town of Ormancik after dark. I slept in a vacant lot and finished the climb in the morning). The magic of this road is the near absence of traffic, the dramatic climatic change one observes between bottom and top and the novelty of being the only cyclist for miles. People will stare at you and cheer and honk their horns in encouragement. Soak up the glory.

Mauna Kea, Hawaii. Rise Over Run: 13,597 feet in 43.1 miles. This biggest of big climbs should top the list, but it comes with a disclaimer: The final three miles are unpaved dirt, ash and gravel and are reportedly almost impossible to ride on a road bike. On the asphalt, which terminates at 9,200 feet above the sea, the highway slants to as steep as a 17-percent grade in places. If you reach the top, savor the strangeness of being in a frigid, treeless Mars-like moonscape—in Hawaii.

Mount Washington, New Hampshire. Rise Over Run: 4,586 feet in 7.6 miles. If bang is elevation and buck is overall mileage, then this route may offer more of the former for the latter than any other paved road. Unfortunately, this legendary climb, considered by many to be the world’s most difficult feat in uphill cycling, is not open to just anyone. The road, which averages 12 percent in grade, is private and is closed to bicycles except during two organized races each year, in July and August. Currently, the July event is open for sign-ups. Note: Registration requires a fee. Cyclists must also arrange for a ride down afterward, as the road is considered so perilously steep that cycling downhill from the summit is prohibited.

Organized bike rides and races that will bust your butt:

The Everest Challenge, Nevada and California. 29,035 feet of climbing in 208 miles, 2 days.

The Death Ride, California. 15,000 feet in 129 miles, 1 day.

The Leadville 100, Colorado. 16,165 feet in 99.3 miles,  1 day.

The Cape Epic, South Africa. 53,460 feet in 488 miles, 9 days.

The Steepest Streets:

Steep city streets are a much different sort of challenge than long highway climbs. They are short, usually a standard city block, but they can be really, really steep, allowing those who go up them some no-joke bragging rights. Consider these nasty, slanty city slopes:

1. Broderick Street, San Francisco. 37 percent.

2. Canton Avenue, Pittsburgh. 37 percent.

3. Baldwin Street, Dunedin, New Zealand. 35 percent.

4. Eldred Street, Los Angeles. 33 percent.

Meadows, lakes, snow and granite are the enduring elements of California's John Muir Trail, which leads through 211 miles of some of the world's most beautiful alpine wilderness. Photo courtesy of Flickr user peretzp

After cycling for weeks, now I’m thinking about walking. Foot travel has been the way of the wayfarer since men and women were still dragging their knuckles. The fact that people still opt to walk today, in the age of the wheel and the combustion engine, tells us there is something virtuous and irresistible in the plodding of one foot forward after the other. And without question, walking works. Using their legs and feet, many people have moved thousands of miles overland, and in many places the trails they wore in the earth are used by modern recreational trekkers who follow in the footsteps of their forebears. Following are five of the world’s great walks—with more to come next week.

Appalachian Trail. Leading 2,181 miles through 14 states and the historic forests and backwoods shanties of Appalachia, the Appalachian Trail was conceived in 1921, and by 1937 it was ready for walking. Today, 4 million people walk parts of the trail every year. Those attempting a through-hike number in the thousands, and only one in four finish. From Maine’s Mount Katahdin to Georgia’s Springer Mountain, the whole package takes as long as six months as hikers accumulate a total elevation gain equal to climbing Mount Everest 16 times.

John Muir Trail. This path through the high Sierra Nevada of California immortalizes the landscape that naturalist John Muir worshiped. And at just 211 miles long through beautiful alpine country, it’s both epic and doable. From the south, the JMT begins at the lower 48 states’ highest peak, Mount Whitney; crosses mountain passes more than 13,000 feet in elevation; traverses some of the world’s most beautiful high altitude wilderness; never touches a road and finally lands hikers in one of the world’s most esteemed natural places, Yosemite Valley. The trail generally requires three weeks from start to finish. If you happen to have a little extra time on either side, you could walk from Mexico to Canada on the Pacific Crest Trail, of which the JMT is just a small part.

Coast to Coast Walk. A walk that doesn’t demand superb physical condition or half a year to complete, this 220-mile path crosses Northern England and leads through the evergreen verdure of the Lake District, Yorkshire Dales and North York Moors National Parks, from the Irish Sea to the east coast of England. Writer and walking enthusiast Alfred Wainswright devised the trail and suggested that hikers touch their toes in the Irish Sea at St. Bees before starting and step right into Robin Hood’s Bay after 10 or 20 days of trudging. Or else it doesn’t count.

Great Wall of China. No, you can’t really see it from space. That was a myth more or less debunked in the past decade or so by astronauts. However, while the Great Wall of China no longer plays a role in international affairs, it makes one heck of a walking platform. Unlike the heavily trammeled Camino (see below) or Appalachian Trails, the Great Wall demands ingenuity, craftiness and durability in anyone who attempts to plod the length of it, which is broken, crumbled or gone in many sections. Australian Mark Scholinz walked the wall in 2007. He encountered frozen steppe country, wolf tracks, endless hospitality and a whole lot of rice and tea.

Camino de Santiago. Once a path of the pious, this European network of trails converges toward its terminus as it leads many thousands of walkers each year to Santiago de Compostela in northwest Spain. Though founded by deeply religious pilgrims more than a thousand years ago, “the Camino” today is simply a recreational venture for most making the pilgrimage. It is also hardly an adventure anymore, as every step of the way has been walked a million times before, with many miles of pathway paralleling freeways and cutting through suburbs and farmland. One highlight of the trail is certainly the Cruz de Ferra, a 25-foot-tall cross which pilgrims have built by depositing knickknacks and trinkets and stones. Today, the rockpile is is almost 20 feet high, a sacred midden built over centuries. It’s truly a wonder just to touch it.

The Cruz de Ferra, surrounded by an ancient mound of stones left by pilgrims, is one of the marvels to be found along the Camino de Santiago. Photo by Alastair Bland

Reading About Walking:

Don’t feel like walking the walk? The armchair is one of the comfiest vehicles of travel we have. You’ll need a good book, and here are several classics of adventure travel.

The Snow Leopard. In this sober account, we find author Peter Matthiessen to be a man of Buddhism, western science, literature and a love of big cats. In 1972, when biologist George Schaller invited him on a 200-mile trek into the Himalaya to track the rare blue sheep, Matthiessen, now in his mid-80s, accepted, unable to resist the opportunity to see a snow leopard. It was the fall, and their trip led into one of the most mysterious, dangerous yet peaceful regions of the world under blue skies and a warm sun. By November, frostbite and blizzards were ever-present dangers. The two Americans, accompanied by Sherpas and porters, do eventually see the blue sheep, while all along the high and rocky trails lurk the haunting signs of the snow leopard.

Danziger’s Travels. English author Nick Danziger points out early in this book that he was not interested in walking a record distance or cycling across a continent when he took up the old trade route of the Asia-to-Europe silk traders. Rather, he utilized whatever local means of travel were available in China, Pakistan, Afghanistan, Iran and Turkey—and often he was walking. Danziger’s travels lasted 18 months, for part of which time he went disguised as a Muslim. The book is an adventure account almost as simple as the travel genre gets, but few are better.

The Places in Between. Journalist Rory Stewart walked for 16 months through Iran, Pakistan, India and Nepal in 2000 and 2001. Then, in the virulent months following the September 11 attacks, he found himself facing Afghanistan. The month he spent walking across it would produce, eventually, one of the best modern travel books I’ve found. Stewart survived on the food and shelter of kind strangers, but many Afghans, hardened by war and the desert, were downright vicious. Stewart was determined to walk, and he firmly refused rides across known danger zones. For part of the way, a trio of Afghan soldiers escorted him. But it’s the many miles he walked alone (and with a great shaggy dog adopted along the way) that make readers marvel, at times, that Stewart lived to write about the trip.

A Walk in the Woods. He’s pudgy. He’s brainy. He has a strange penchant for stupid knickknacks and trivia from his Americana Midwest childhood. And for some reason, late in the 1990s, he decided to walk partway across America. In the end, comic Bill Bryson only completed, in bits and pieces, 800-some miles of the Appalachian Trail, but it was enough to provide him with the fodder he needed to write one of the funniest travel books of our time.