Hang-gliding in Rio de Janeiro, Brazil.
Tim Clayton

Extreme Vacations: 10 Adventures for Active Travelers

Looking to add a shot of adrenalin to your next vacation? The last few decades have seen an explosion of new ways to explore the outdoors that will have your heart pumping and your eyes open wide. These ten sport adventures will let you come home with a story to remember, and perhaps a new passion.

Photo Caption: Hang-gliding in Rio de Janeiro, Brazil.
Base jumping off the Kjerag mountain in Norway.
BASE Jumping
What do you try when sky-diving becomes a bit of a yawn? Meet BASE jumping, one of the world's most notoriously dangerous sports.

BASE is an acronym that describes the fixed point from which you start your freefall: buildings, antennas, spans, and earth (e.g., cliffs or mountain tops) can all act as substitutes for an airplane. While people have been attempting to jump off buildings such as the Eiffel Tower for at least a hundred years (often with fatal consequences), the practice caught on in the 1970s when a skier launched himself from Yosemite's El Capitan cliff with a parachute, followed by jumps in 1975 from Toronto's CN Tower and the south tower of the World Trade Center. By 1978 a BASE jump had appeared in the James Bond film The Spy Who Loved Me and expert skydivers were starting to make regular leaps from El Capitan while filming their exploits.

Because a BASE jump starts from a much lower elevation than one from an airplane, you have much less time to deploy your parachute (and save your life) -- sometimes only a few seconds. Participants must be expert sky-divers (most have made hundreds of airplane jumps) and use a specialized parachute. The risk of injury is high -- according to one study, about 1 in every 250 jumps result in injury (often serious), and 1 in 2,300 jumps is fatal.

The high level of risk means that BASE jumping is usually illegal, but there are a few places that have embraced the sport. One of the most popular is Kjerag mountain in Eastern Norway. Jumpers can drink in a spectacular view of the 26-mile long Lysefjord before plunging 3,200 feet from the top of a cliff. More than 29,000 jumps were performed over 15 years at the site.

Photo Caption: Base jumping off the Kjerag mountain in Norway.
Bungee jumping from the Kawarau Suspension Bridge at AJ Hackett Bungy in Queenstown, New Zealand.
Lisa Wiltse
The tiny South Pacific nation of Vanuatu has few claims to fame, but the most significant may be the modern adventure sport that it inspired: bungee jumping.

For perhaps hundreds of years, Vanuatu youth would plunge from wooden platforms with vines tied around their ankles as a rite of passage into manhood. A BBC film crew recorded this ritual in the 1950s, which inspired a few experimental jumps by Oxford University's famed "Dangerous Sports Club." A film of those jumps in turn inspired New Zealander AJ Hackett, who launched the first commercial bunjee jump from Kawarau Bridge in Queenstown, NZ.

While jumpers were originally attached to the bungee cord by their ankles, most operators now also use a body harness for additional safety. Most jumps take place from either bridges or cranes. When a jumper falls, they get several seconds of free fall before the elastic cord begins to stretch, and the jumper slows down until the cord reaches full stretch, at which point they fly back upwards, usually bouncing several times until all the energy of the fall has disappeared.

Want to feel like an action hero? One of the highest commercial bungee jump operations is at Verzasca Dam near Locarno, Switzerland. It became famous after a stuntman jumped from the top of the dam (720 feet) in the opening scene of the James Bond movie GoldenEye -- which some have called the best movie stunt of all time. Since then more than 10,000 people have duplicated the feat.

Photo Caption: Bungee jumping from the Kawarau Suspension Bridge at AJ Hackett Bungy in Queenstown, New Zealand.
Hang-gliding in Rio de Janeiro, Brazil.
Tim Clayton
Hang Gliding
Fans of hang gliding love the ability to soar thousands of feet above the earth with a simple device that's basically a sail fastened to an aluminum frame. Who do we have to thank for such an elegant design? NASA, of course.

Back in the early days of the space race, the flexible wing design of modern hang gliders was pioneered by NASA as a way to help recover space capsules returning to Earth. Design evolutions in the early '70s lead to mass popularity for the gliders, with glowing press coverage from magazines like Popular Mechanics and Life.

If you can jog while balancing a 50-70 lb. weight on your shoulders you can learn to fly. While you'll start on tandem flights with an instructor, you will soon be able to fly solo from the training hill and progress to higher flights, all in two days. Flights are controlled by shifting the pilot's weight with respect to the glider. Hang gliders routinely stay aloft for 3 hours or more, and can climb to elevations of 15,000 feet.

Launching can be as simple as jogging down a slope and gliding away from the mountain, or leaping from a cliff top -- if you're lucky, into a breathtaking backdrop like Rio de Janeiro. Rio is one of the preeminent places on Earth for hang gliding, with ocean breezes that lift up over the Sierra do Mar mountains and create near-perfect conditions for liftoff. Your flight will probably begin on a tall ridge in Tijuca National Park, one of the largest urban rainforest parks in the world, where toucans and monkeys are common sights. Once you're aloft, there's nothing between you and the lovely statue of Christ the Redeemer, the spires of Sugarloaf Mountain, and the sparkling sapphire Atlantic, except a balmy tropical breeze.

Photo Caption: Hang-gliding in Rio de Janeiro, Brazil.
Zipline at Haleakala, Maui. Photo: Skyline Eco Adventures
Courtesy Skyline Eco Adventures
Never wanted to hug a tree? After zipping between them at over 50mph, attached to a thin cable several stories above the ground, you may change your tune.

While variations of ziplining's rope-and-pulley system have been around for over a century, it was graduate students researching the rainforest who were the first to combine it with rock climbing equipment so they could better explore forest canopies in the '70s. Entrepreneurs soon got wind of the idea and by the early '90s the first canopy tours were operating in Costa Rica. Operations have since sprouted across the globe, giving travelers the chance to explore beautiful natural wonders at nerve-jangling speeds. The original canopy tours are still very popular, but zip lines are also used to fly above palaces in India, over a cliff in Alaska, or skirt the Great Smoky Mountains attached to two of your friends.

Photo Caption: Zipline at Haleakala, Maui. Photo: Skyline Eco Adventures
Whitewater rafting down the Colorado River in the Grand Canyon, Arizona.
Whitewater Rafting
When explorers first traversed new lands via inland waterways, uncharted whitewater rapids often induced either a long, cumbersome circumvention by land or a panicked crossing where capsizing into turbulent waters was not uncommon.

While today's inflatable rubber rafts have improved safety dramatically, they've done little to dull the excitement. Rapids are rated on a scale of Class I (calm, with little rough water) to Class V (big waves, rocks and/or drops), with many of the most popular tours blasting through Class IV and V. Boats usually hold between 4 and 12 paddlers, plus an experienced river guide who barks instructions that may keep you from falling in but certainly won't keep you dry.

The Grand Canyon is known as the birthplace of modern river tripping, and its rapids are legendary -- in part because there are 161 significant ones to cross if you have the two weeks it takes to traverse the entire thing. The names of the rapids reflect the stark landscape -- Granite, Hermit, Crystal, Lava -- and when you're not paddling for your life you'll be marveling at the beauty of the steep canyon walls. At night, you'll look up at the starry sky while the gurgling of the Colorado River lulls you to dreams of the next day's adventures.

Heli-skiing in British Columbia.
If you've ever watched any of those extreme-skiing movies where solo skiers gracefully slice through virgin powder and drop over cliff edges onto wide, empty mountain slopes you may have wondered -- how can I do this?

The answer: heli-skiing. When groomed trails no longer excite you, or you long for one of those only-in-the-movies moments, your dream is only a helicopter ride away. At a typical operation, you'll be whisked to the mountain top with a group of 4 to 12 skiers and a guide, and you'll get anywhere from 6 to 12 runs in during the day -- skiing 10,000 vertical feet is just an average day. The terrain can vary from high glaciers to alpine bowls, steep chutes or glades of snow-laden trees. At many places, all you need is the skill to consistently ski intermediate or advanced resort runs and a fat wallet -- these tours will typically set you back close to $1,000 per day.

The Bugaboo Mountains of British Columbia (just west of the Rockies) is where heli-skiing started in 1965, and today it is by far the most popular site for the sport. Multiple companies operate here, offering distinct trips oriented to everyone from first-timers to highly experienced heli-skiers, and even women-only groups. At night, you relax in a five-star lodge where the quality of the food is as exceptional as the skiing.

Photo Caption: Heli-skiing in British Columbia.
Canyoneering at the Escalante National Monument in Utah.
In certain places, the names give away what you're about to encounter. With canyoneering (or canyoning) they also tell you to pay attention -- think places like Death Hollow, Hell's Backbone and The Devil's Garden.

Canyoneering really refers to an amalgam of skills -- hiking, scrambling, climbing, jumping, rappelling, and swimming -- used to traverse narrow canyons. It's also a thrilling way to explore some of the planet's most rugged and remote wilderness landscapes. The inaccessibility of the terrain and potential for falls brings with it inherent dangers (as seen in the movie 127 Hours), so good navigational skills and proper safety equipment are essential.

While the sport can now be found in dozens of countries, it started in the narrow slot canyons of Utah's Zion National Park, with the advent of modern climbing equipment in the 1960s. Today, southern Utah is still the epicenter for this type of wilderness exploration. Grand Staircase/Escalante National Monument covers 1.9 million acres of some of America's most remote backcountry, and the canyons are as narrow as eight inches in some places, and glow with a palette of pinks, oranges, blood red and gold. Canyoneering here involves wading through ice-cold pools, scrambling over smooth slickrock, and squeezing your frame through narrow slot canyons. You might see another hiker or two, but most of your companions will be lizards, eagles, jackrabbits, and the indescribable beauty and silence.

Photo Caption: Canyoneering at the Escalante National Monument in Utah.
Mountain biking downhill along Yungas Road in La Paz, Bolivia.
Downhill Mountain Biking
While many adventure sports lend themselves to hyperbolic claims, these rarely originate from banks. But such is the case in Bolivia, where the normally tight-lipped Inter-American Development Bank called out the narrow Highway 3 that traverses the Andes northeast of La Paz as the deadliest road in the world. Mountain bikers listened and took it as a challenge.

Racing a mountain bike downhill is a fairly simple sport -- all you need is a bike, gravity and little common sense -- but variations abound around the globe, from hurtling past villas in the Italian Alps to struggling to tear your eyes from the jaw-dropping scenery in the Colorado Rockies. What they have in common is a great way to experience wide swaths of nature and learning first-hand what a white-knuckle grip looks like.

On Bolivia's Death Road (as it is now commonly called), more than 30,000 cyclists have completed the 40-mile trip, but a dozen or so have not (along with hundreds of motorists). It's amazing that the number of fatalities is as low as it is considering that in many places along the five-hour ride the "road" is a dirt pathway just a few feet wide and strewn with large rocks, slathered with muck from rain and waterfalls, and dotted with crosses. Did we mention that you'll descend 11,000 vertical feet and there are no guard rails? Check your brakes before you go and watch out for passing vehicles.

Photo Caption: Mountain biking downhill along Yungas Road in La Paz, Bolivia.
Volcano surfing on Cerro Negro in Leon, Nicaragua.
Volcano Surfing
Sometimes creating a new adventure sport is as simple as adding two cool, but seemingly unrelated, things together and see what happens. In Nicaragua this became volcanoes + surfing = volcano surfing. Voilà, a new way to risk life and limb is born.

In truth, volcano surfing owes more to tobogganing than surfing. Participants spend 45 minutes climbing the steep incline to the crater's edge, don bright orange jump suits and goggles, then jump on a plywood sled. With a push they are hurtling down the 40-degree slope, the board scraping against the harsh volcanic charcoal that creates a deafening noise as they hit speeds of 50mph. Some riders get scared and try to brake -- a big mistake that usually results in them tumbling in the hot dust and stones, board skittering ahead of them. Savvy riders go with the flow and reach the bottom of the 2,400-ft. mountain in a few minutes.

The volcano, Cerro Negro, is the most active volcano in the Americas, having erupted 20 times since 1850, the last being in 1999. It's located about 15 miles northeast of the pretty university city of Léon, where you can swap stories of your bravado at one of the city's many excellent bars.

Photo Caption: Volcano surfing on Cerro Negro in Leon, Nicaragua.
Zorb globe riding at the Agrodome in Rotorua, New Zealand.
Tim Clayton
Many extreme sports require a significant degree of skill or courage, or both. And then there's Zorbing.

Founded in New Zealand's adventure sport hotspot of Rotorua in the mid-90s, zorbing puts you in the center of a gigantic plastic bubble made of clear plastic and then sends that bubble -- with you inside it -- rolling down a steep hill. (Some operators put you on a level surface, giving the rider more control, but what's the fun in that?) You'll enter the Zorb head-first through its "mouth" after taking off your shoes and jewelry. A smaller sphere rests inside an outer sphere, and the air space between them helps absorb the shocks you'll feel when you hit bumps at 20mph (32kmph). To add to the fun, you can strap yourself in with two friends and see who has the weakest stomach.

The founders have franchised the concept so that you'll now find it in over a dozen countries, but the original site in Rotorua -- where you can also try sky diving, white water rafting and bungee jumping -- still has some of the best facilities. The adjacent sulphur-smelling Lake Rotorua, according to the company website, smells like rotten eggs and will enhance male sex drive (but probably won't make you more attractive).

Expect to see more of this oddball sport in the next couple of years -- Zorbs have been adopted as a symbol of the 2014 Winter Olympics in Sochi, Russia.

Photo Caption: Zorb globe riding at the Agrodome in Rotorua, New Zealand.