are numerous even in the dark zone, with individuals having been sighted amongst boulders and within fissures in the granite.

Krubera Cave in the republic of Georgia is currently the deepest known cave, at 7,208 feet. But Dark Star, with so many areas still to survey, is a prime candidate to take over the title.

So the expedition also made it a goal to publicize the importance of blue holes and the threats they face. Veteran cave diver Brian ... inland blue holes—deep, dark, sheltered, with little ...