Mysterious craters may have been home to an ancient cult.

3,000 market stands in five former Zeppelin hangars.

A black cat protests the City Guild in Riga's Old Town.

A former Latvian headquarters of the brutal KGB secret police is now open as a grim reminder of their atrocities.

A subterranean house of worship carved right out of the bedrock.

The Guardian of Tallinn.

"There's nothing there," and other lies the KGB told us.

This medieval Estonian tower provides access to a series of tunnels that have been home to soldiers, punks, and fine art.

An abandoned Jazz Age dream home and con man's hideout in Death Valley.

"Only the devil could play golf here."

Millions of years of oxidation make a drive down this winding Death Valley road surprisingly colorful.

The lowest point in North America is home to an undrinkable pool surrounded by fields of geometric salt flats.

An architectural statement of artistic intent smack in the middle of Providence, Rhode Island's Colonial uniformity.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

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

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Steadily reminding Czechia of its past.

Macabre astrological automaton clock dating to the late 1400s.

The twin towers in this Chicago fountain use 50 foot tall video screens to spit on people.

A former waterfront market is now in the center of town due to some interesting Boston engineering.

The site of one of the strangest disasters in history—a wave of deadly molasses traveling at 35 mph.

Mysterious 500-year-old tapestries depict a unicorn hunt.

Blighted Irish field and the ruins of a 19th-century cottage on the edge of urban Manhattan.

A semi-scholarly approach to sex.