I knew that once we left the brightness of the sun, the interior of Fingal's Cave would be dark. Its hexagonal stones would progressively suck away daylight as we floated back into the very heart ...

Natural "skylights" cut through the cave's dark interior where dust and other particles float like they are suspended in spotlights of sunshine. Because of this, Skylight Cave is the kind of place ...

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.