The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

An unusual round church in London with a Templar past.

This futuristically sylvan church is a glass-enclosed marvel of modern architecture.

The largest earthwork effigy in the world.

An Australian lake whose pink hue defies scientific explanation.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

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

Tour the sci-fi-esque reality of governmental disease management.

A whimsical village of unique treehouses resides in a Washington forest.

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

Eighty million natural history specimens call this gargantuan museum home.

These eerie outliers of the lightning bug family glow a mysterious blue color.

No one knows how this Pacific Northwest spruce tree came to have so many trunks.

An ancient capital city that dates back 3,000 years old and harbors many surprises.

This incredible collection of vintage pinball machines can be played at 25 cents a pop.

A castle that was built stone by stone by an eccentric journalist.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

One of the dwarven trees dates back to 1625 and survived the Hiroshima bombing.

The angel of death appears to weep black tears at this grave marker.

The most visited, and possibly most controversial, museum in Germany.

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

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

Famously misunderstood wonder of the ancient world

One person's lost luggage is another person's treasure.