On the Oregon coast there is a natural hole that seems to be draining the sea.

The largest natural travertine bridge in the world is nestled in a small canyon in central Arizona.

A museum dedicated to the alleged Roswell Incident.

Twenty-seven massive radio antennas on the high plains of New Mexico search for life on other planets.

Colorful Native American paintings are hidden within this small cavern.

Ancient human, animal, and geometric figures drawn in the earth.

The now-abandoned tunnels were built for the transcontinental railroad on the route where the first wagon train entered California.

A once-booming Mississippi River town with a history of racial violence is now eerie and mostly abandoned.

Colorful boxes placed over the dead are left to rot and crumble.

The easternmost town in Alaska can only be accessed from Canada.

The world's largest squirrel statue clutches a pecan bigger than your head.

The fading, forgotten remains of a once bright and booming factory.

A popular 19th-century natural landmark is now hidden within a sprawling forest.

In a 345-million-year-old cave that's 200 feet underground, dinner awaits.

The only surviving fragment of the lost Narragansett Pier Casino.

An office built to look like a giant basket.

This mysterious artificial cave has long puzzled New Englanders.

The world’s largest Masonic temple was saved by the White Stripes.

This quaint Italian town keeps losing ground as the sides of its plateau slowly erode.

The entire length of the border is marked by a 20-foot-wide slash through the trees.

The location of Puerto Rico's first water bottling plant, thanks to a collaboration between Mother Nature and technology.

This recently restored crypt was once plagued by liquefying coffins and exploding caskets.

Historical figures from New York City's Catholic community reside in Midtown.

This spectacular track has run continuously since 1882.