This incredible natural wonder is located in Naica, Mexico. The Giant Crystal Cave is a breathtaking subterranean cave filled with some of the largest and most spectacular crystals ever discovered. The crystals range in size from a few centimeters to over 11 meters in length, and some are estimated to be over
From Wikipedia
Cave of the Crystals or Giant Crystal Cave is a cave connected to the Naica Mine at a depth of 300 metres (980 ft), in Naica, Chihuahua, Mexico. It takes the form of a chamber within the limestone host rock of the mine, and is about 109 metres (358 ft) long with a volume of 5,000 to 6,000 cubic metres.