Mexico's Cueva de los Cristales (Cave of Crystals) contains some of the world's largest known natural crystals—translucent beams of gypsum as long as 36 feet (11 meters).
Hang Son Doong, Viet Nam The world's largest cave. A 1/5 mile block of 40 story buildings can fit inside. One of the only caves with a jungl
Places & Spaces