Explore the ancient caves of Hang Son Doong, Vietnam. Hang Son Doong is one of the largest caves in the world and features a fast-flowing underground river. For spelunkers, exploring Hang Son Doong is the equivalent of scaling Mount Everest.
Ooh, a Sunday post! When Lydia and I were planning our trip to Bermuda the one thing we both knew we *had* to do was see the crystal caves. If you know me well, then it’s probably no surprise to you that I had a pretty killer rock collection .
Mammoth Cave, United States-Mammoth Cave National Park preserves the cave system and a part of the Green River valley and hilly country of south central Kentucky. This is the world's longest known cave system, with more than 400 miles explored.