Ice cave in the Skaftafell National Park in Iceland. Ice caves collapse and new ones form as each glacier grinds slowly towards the sea. Local guides can help you (without dying) find one. (Visit Skaftafell National Park in Iceland.
Temple Entry, Japan photo via amy. Hard to believe the same nation that perpetuated the rape of Nanking and the Bataan Death March, also gives us rock gardens and some of the most beautiful and tranquil places on earth.
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.