Over thousands of years, this slot canyon was carved out of the bed of an ancient lake.

The perfectly named cave drop is the deepest in the continental United States, almost matching the height of Seattle’s Space Needle.

A bizarre roadside attraction and the first instance of miniature golf in the world.

This large cave is a summer home to thousands of bats and has a rich history dating back to prehistoric times.

This simple gravestone remembers a pig who single-hoofedly raised $19,000,000 for the Navy.

A beautiful geyser under environmental threat.

This Yellowstone geyser may not shoot as high as the nearby Old Faithful, but it erupts for considerably longer.

The only natural lake in the world that drains into both the Atlantic and Pacific Oceans.

A 6th-century stone lies at the site of the mythical battle waged between King Arthur and his nemesis Mordred.

An experimental, automotive replica of Stonehenge.

Underneath downtown Lincoln resides a network of caves that was also the city's first brewery.