Tucked into a collapsed volcano in southern Oregon sits the deepest lake in the entire United States, famous for its almost unreal shade of blue. What is it called? Lake Tahoe Crater Lake Lake Chelan Flathead Lake None Beneath the rolling hills of central Kentucky lies the longest known cave system on the planet. By what fitting name is this underground giant known? Carlsbad Caverns Luray Caverns Mammoth Cave Wind Cave None In the San Luis Valley of Colorado, against a backdrop of snowy peaks, you'll find the tallest sand dunes in North America. Which national park protects them? Great Sand Dunes National Park Death Valley National Park White Sands National Park Mesa Verde National Park None This dramatic rock formation rising over the plains of Wyoming holds a special place in history: in 1906 it became the very first of its kind in America. What is it? The first national park The first national monument The first state park The first wildlife refuge None At a quirky Wisconsin attraction, there's a glass-walled room that juts hundreds of feet out over a wooded valley with nothing holding up its far end. What is this gravity-defying room called? The Sky Bridge The Glass Gallery The Infinity Room The Crystal Wing None Stumper. Near a small town in West Texas, mysterious glowing orbs have appeared on the horizon for well over a century, dancing and changing color with no agreed-upon explanation. What are they called? The Roswell Glow The Marfa Lights The Big Bend Beacons The Pecos Flames None Time's up