A stunning, two-tiered waterfall made famous by poets, artists and the legend of a ghost dog.

A semi-scholarly approach to sex.

This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.

For two weeks every June, fireflies in the Smoky Mountains perform an astonishing light show.

A one-of-a-kind collection of a unique medium.

A collision of human error and natural geothermal pressure created this rainbow-colored geologic wonder.

Dramatic river bend surrounds a natural red-rocked pedestal.

The design of this historic domed church was influenced by Thomas Jefferson and intended as a statement of religious freedom.

Several times a year, during low tide, two pairs of historic train tracks are revealed on this New Jersey beach.

Hundreds of glow-in-the-dark objects light up a museum in a historic zinc mine.