The last moments of the ill-fated Pompeiians, frozen forever in plaster.

This abandoned Navy base was transformed into an off-grid alternative living community for thousands of people.

The ghost town that ended up on Ebay.

These delicate buggers are some of the rarest fossils that have bubbled up from the Tar Pits.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

A collection of 20th-century automata, penny arcade games, and musical contraptions.

This historic "City of the Dead" lies prominently in the center of New Orleans' famous Garden District.

Aqueducts have dramatically changed this old lake, now home to tufa towers and its very own species of tiny brine shrimp.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

Tubing through a cave lit with glowworms is a magical underground experience.

The magic's in the hole!

San Francisco's newly reopened hands-on science museum.

A collection of oddities including Dr. Kevorkian's suicide device, the Thanatron.

The longest continuous lava tube in the continental U.S. offers 2.5 miles of dark explorations for the adventurous.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

Home to items never before seen by the public.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

Northern Ireland's Brobdingnagian stepping stones.

Stepping away from the glitz of mobsters and casinos to learn about the other history of Vegas.

A hand-built folk art installation covered with messages of God's love.

The ghostly remains of an accidental sea.

A snapshot of the city's fascinating voodoo culture.

A heavenly experience, right here on Terra Firma.