Nowhere on Earth is as rich in quantity and quality of the prehistoric creatures' remains as the Badlands' arid Dinosaur Provincial Park, a UNESCO World Heritage site where digs are still under way.

Badlands National Park is full of geological oddities, but the 1.5-mile-round-trip Notch Trail is one of the best treks in the South Dakota park. There's something distinctly eerie about the Badlands.