Built To Thrill: 12 Crazy Man-Made Adventures

Especially now that summer's upon us, there's nothing quite like catching the wind in your hair, reaching out for the next rock hold high above the valley floor, or whizzing down some woodsy trail on your finely tuned mountain bike... well, almost nothing.

Click here to see 12 amazing man-made adventures.

The outdoors are undpredictable, after all. Sometimes the sun is too hot, not hot enough, or hiding behind soggy clouds. Weather aside, maybe you don't have enough saved for another skydive. Perhaps you've always wanted to explore, Little Mermaid-style, under the sea, but you're deathly afraid of sharks or, worse still, nowhere near the ocean. As great as the outdoors are, braving them means dealing with all of these potential risks and unknowns.[slideshow:692]

Lucky for us, humans are meddling creatures. Rather than leave well enough alone, we've found ways to recreate natural features like ski hills, coral reefs and even whitewater rapids. By engineering our own adventures, we bring a degree of control and predictability to even the wildest adrenaline sports (plus make them accessible whenever and wherever we want—mountain biking in January, anyone?). Many of these adventures are great for first-timers who aren't yet confident in their skills, or who aren't quite ready to invest in pricey gear, like a full SCUBA setup. Others just offer up made-to-order adrenaline rushes and you-can't-believe it thrills.

We've rounded up 12 of the greatest man-made adventures on the planet, including awe-inspiring (and entirely safe) wildlife encounters, outdoor thrills brought indoors and amazing "natural" features that were deftly built with human hands. From a transplanted marshland safari in the heart of the Netherlands, to a cool indoor ski center under the steaming Dubai sun, all the way to a barnacled sunken warship, teeming with marine life—here are some of the wildest man-made adventures available.

What wild experiences have humans built? Click through to see.