Under a swath of Kentucky hills and hollows is a limestone labyrinth that became the heartland of a national park. The surface of Mammoth Cave National Park encompasses about 80 square miles.

The national park forms one unit of the North Cascades National Park Service Complex. The two other units—Ross Lake National Recreation Area and Lake Chelan National Recreation Area—contain ...

The creation of three "dire wolf" pups has raised hopes that it may be possible to resurrect extinct animals. But some scientists have grave concerns. Swathes of scientific data deletions are ...