The glowing blue Nymphaeum of Emperor Tiberius.

The largest drain hole in the world.

Eons ago, a rushing lava river formed this pristine passage through solid rock.

An alleyway plaque is all that remains of the independent Texas' envoy that forgot to pay their rent for over a century.

The sci-fi villain is a little-known inhabitant of the U.S. capital's largest cathedral.

Mural made of 100,000 pieces of hand blown glass, and until recently, the largest glass mural in the US.

Remnants of a Victorian garden feature sitting in public woodland.

The yawning maw of this pagan visage is said to bite off the hands of liars.

Abandoned bridge hidden deep in the San Gabriel Mountains.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

One man's vast collection of artifacts and ephemera from matchbooks and postcards to vintage neon signs and cars.

Standing in a state of "arrested decay," this ghost town allows for a detailed peek into Gold Rush life in an unusually harsh climate.

The underground sanctuary of a mysterious ancient cult.

Make your reservation to have coffee with some kitties.

The final resting place for the remains of 143 Habsburg royalty.

See massive fossils that are over 200 million years old in northeastern Arizona.

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

An outdoor sculpture park of giant pink robots and post-apocalyptic Christmas scenes.

The hallucinogenic center of the ancient world.

Visible below the waves are memorials to the city's Gold Rush dead.

A floating cat sanctuary on an Amsterdam canal.

Stripes of flowers bloom each spring in a 50 acre rainbow of color.

Costumed elves and mountain bikers co-exist peacefully at this abandoned Christmas-themed adventure park.

Enormous piles of historically significant stones, dumped by Congress in a forest, and abandoned for 60 years.