The world is full of fascinating and unique caves that beckon the adventurous traveler.
This behemoth is the world's largest cave, boasting chambers so vast they could fit entire city blocks.
Imagine a cavern filled with giant, translucent crystals, some as long as 30 feet.
Take a boat ride through a network of caves illuminated by thousands of tiny glowworms, creating an ethereal, starry night sky underground.
Kayak through turquoise waters amidst towering marble cliffs and cathedral-like caverns in this Patagonian wonderland.
This mysterious sinkhole appears like a bottomless pit, especially when the ocean surges and sprays mist high into the air.