The World's 15 Craziest Zip Lines

Pleasures don't come much simpler than a zip line. But something magical happens when you stretch a cable over a great span and glide—using only gravity and a harness—across a gorgeous natural landscape like a bird on the wing. [slideshow:714]

Historically, zip lines were purely functional, often used to deliver goods across great distances in mountainous countries. Then, in the 1970s, researchers in Costa Rica began to realize the potential of these cables and began stringing them up through the rainforests as a way to get around more quickly and easily. It wasn't long before they started to see the great tourism potential of their newest mode of transportation, which allows for both an adrenaline rush and a great learning experience. 

Click here to see 15 gnarly zip lines from across the globe.

Enthusiasts will assure you that riding on different zip lines can be like tasting the subtle nuances in unique bottles of wine. Thanks to variables like length, height, altitude, angle and speed, each zipline has its own character. You might encounter one that's meandering, scenic and family-friendly. Or, like a barrelling roller coaster with a one-track mind, there are others that are speed demons, rushing back to Earth at up to 100 mph.

And, like in real estate, it's all about location, location, location. Once confined to tropical destinations like Central America, commercial zip lines and canopy tours made their way to America for the first time in 2002. Now you'll find them everywhere from a slate quarry in Wales to an underground mine in Kentucky to a former Olympic stadium in Utah to an archaeological park surrounding Angkor Wat

We've collected some of the longest, fastest, steepest and most unique zip lines in the world—now get zipping!

Click here to see 15 gnarly zip lines from across the globe.