This modern castle sat empty for decades before a fire inspired its builders to complete its luxury halls.

One of the few surviving "Wigwam"-themed motels.

Prehistoric animals decorate this popular outdoor park.

This former tuberculosis research hospital endeavored to cure the dreaded disease with fresh air and positive attitudes.

The world's longest known cave system.

A recreation of the doomed ocean liner in the middle of the Smoky Mountains.

148 feet long and in the middle of a verdant forest.

This architectural triumph is the only Frank Lloyd Wright house in Alabama.

A clock set into the concrete outside a Manhattan jeweler has been telling time underfoot for over a century.

A dilapidated dock tells the story of Titanic’s missed arrival.

Originally a brothel during the Klondike Gold Rush, this bar once used dolls to denote when ladies were working.

The facade of this relic from the Klondike gold rush is decorated with over 8,800 pieces of driftwood.

A historic freight system that found the true gold rush is in tourism.

A rare chance to get up close and personal with a 13-mile ribbon of ice near downtown Juneau.

A tunnel of hardened lava along Maui’s famous Road to Hana.

This World War II-era bunker is now packed with posters and props from movies and TV shows filmed nearby.

This former luxury resort in Kaua'i is now an abandoned relic.

Once the site of the Hawaiian monarchy, this building was originally designed as a palace.

This narrow coastline trail through the dense Kauai wilderness is among the most beautiful and dangerous in the world.

This blowhole is supposedly caused by a trapped monster.

The only royal palace on U.S. soil has been a territorial capitol, a military headquarters, and a prison for a queen.

This industrial area was the dumping ground for massive amounts of trash, some of which washes up as tiny bits of sea glass.

Race through the maze, get your name on the sign.

Watch the newest land on the planet form before your eyes.