The Waitomo Glowworm Cave is a cave on the North Island of New Zealand, known for its population of glowworms, Arachnocampa luminosa. These glowworms spin a nest out of silk on the ceiling of the cave and then hang down. Then, the larva glows to attract prey into its threads, so that the roof of a cave is covered with larva can look remarkably like the heavens at night.
Belize ... This is called the ATM Tour or ATM Cave. It's amazing, you swim in with headlamps on and climb rocks and ladders to get to different levels. On each 'platform' you observe different artifacts. It's pitch dark inside with flowing water. Once in a lifetime tour, there are 25 guides that go through special training to be allowed to take tourists in the cave.
Škocjan Caves, Slovenia by hk_traveller, via Flickr. International scientific circles have thus acknowledged the importance of the Škocjan Caves as one of the natural treasures of planet Earth. They represent the most significant underground phenomena in both the Karst region and Slovenia.