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River Styx

Mammoth Cave, Kentucky, USA. Source: Margaret River/CC BY ND 2.0

Mammoth Cave: An Underground Attraction That Sparked a War in Kentucky

No remains of mammoths have been found in the underground maze called Mammoth Cave - the name refers to the sheer size of its entrance. Mammoth Cave National Park in Kentucky, USA, is a remarkable...
The Hellfire Caves of West Wycombe

The Hellfire Caves of West Wycombe

The Hellfire Caves of West Wycombe are a network of man-made chalk and flint caverns in Buckinghamshire, England, made famous by their sordid past. They are named after the infamous Hellfire Club,...