This sinkhole in the Arizona desert is filled with carbonated, arsenic-rich water

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

A colorful square marks the heart of the city's LGBTQ community.

A grassroots community effort in the 1970s led to the creation of this beautiful garden full of delightfully whimsical exhibits.

The largest cemetery in the American Southeast is a hidden gem near the heart of Atlanta.

The only subterranean ping pong table in Atlanta.

This abstract roadside poultry was saved from demolition by outraged drivers and pilots.

This spectacular dome managed to survive after being bombed in World War II, in an event known as the "Miracle of Mosta."

The floor of this spectacular Baroque sanctuary is covered in memento mori.

This church is named for one of the most dramatic tales in the early Christian church.

A 1970s resort city now stands abandoned, caught in the middle of a divided island.

This no man's land slicing through the island is strewn with abandoned relics of another time.

The largest caravanserai in Cyprus also includes amazing examples of Ottoman architecture.

A museum marks and documents the site of the Titanic's launch.

These engineering masterpieces are a dominant feature of the Belfast skyline.

These barriers stand as stark reminders of Northern Ireland's troubled past.

It was once nicknamed "the most bombed hotel in Europe."

The only monument to name all of the passengers and crew who died on the RMS Titanic.

The smaller of the three towers of San Marino is a former prison inaccessible from the ground level.

Art Nouveau painter Alphonse Mucha spent 18 years creating these monumental paintings of Slavic history and mythology.

A monument to the bloody fight against fascism in Slovakia during World War II.

The palace window through which Protestant nobles flung two Catholic regents, thus sparking the Thirty Years' War.

Steadily reminding Czechia of its past.

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.