A gothic palace of endless stalagmites and pseudoscorpions waits within one of the world's most beautiful caves.

This super steep hike ascends 2,000 feet in less than a mile.

Earth's tallest volcano is sacred to Native Hawaiians, and home to a dozen world-class observatories.

Come for the speed, leave in love with the desert.

This $3 million model train takes you through Chicago, Seattle, and the thousands of miles in between.

The country's oldest continually-operated mini golf course lies hidden in plain sight, eclipsed by one of D.C.'s most popular tourist attractions.

A sculpture for the sun and stars, created by Nancy Holt.

The tallest outdoor elevator in Europe rockets passengers on a dizzyingly precarious ride to the top of a mountain.

Twice a year, visitors can tour the desolate site that birthed the Atomic Age.

A remote candy-striped mountain in the Peruvian Andes straight out of the pages of Dr. Seuss.

This concert pavilion on the shore of the Great Salt Lake has been destroyed by fire, water, and disinterest but keeps coming back.

Once the "Eighth Wonder of the World," this iron railroad bridge was decimated by a tornado.

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

The world's most remote permanent settlement on an active volcano.

Remote, volcanic island that Darwin, Hooker, and the Royal Navy shaped into a thriving, artificial ecosystem.