America's vast and diverse landscape is obviously incredible to witness aboveground. But descending just below the surface, you can find some equally amazing (if dark and stuffy) natural wonders ...

Flanked by the Mississippi River to the east and the Missouri River to the west, this bountiful state formed part of the backbone ... caves. You’ll find this famous natural landmark of Iowa, Maquoketa ...

An investigation continued Saturday into the discovery of a body at Lake MacBride State Park in Johnson County, Iowa, ...

Laurel Caverns, the largest cave in the northeastern U.S., is set to become Pennsylvania's 125th state park. The cave, ...

Laurel Caverns, the largest cave in the northeastern U.S., is set to become Pennsylvania's 125th state park. The cave, currently owned by the Laurel Caverns Conservancy, will be donated to the state.