These 2000 year old remains of a Roman aqueduct are hidden inside a hotel lobby.

Once a luxurious flagship of the Soviet Union, this Brutalist structure remains a landmark of Tashkent’s communist past.

This Old West hotel, the longest in continuous operation in the state of Arizona, is claimed to be haunted.

A ceramic-tiled room at the Seelbach Hotel said to have secret tunnels used by Al Capone and a crowd that helped inspire F. Scott Fitzgerald's 'The Great Gatsby.'

These beautiful castle ruins are nestled in the Polish countryside.

These crumbling ruins are all that's left of the ancestral home of Clan Crawford.

This 3,000-year-old “opium black fortress” towers over the ancient town named after it.

This log house sits in the remote Canadian wilderness, and holds a mysterious tale of the trapper who built it.

Northern Europe’s largest castle ruins sit precariously on an island cliffside.

The ruins of this magnificent Scottish castle blend both Gothic and Renaissance architectural styles.

In 1977, an eccentric book lover formed a micronation for book lovers.

A place steeped in history that may be best known as the set of a 1960 film.

Inside a Scottish castle hangs the tattered remains of a flag with murky origins and supposed magic powers.

The castle that provided the setting for much of 'Monty Python and the Holy Grail' is now a pilgrimage site for fans.

This ruined castle is said to be the legendary keep of a Viking princess.

The eerie remains of one of Ireland's oldest castles, said to be haunted by the ghost of a woman who brings ill fate.

This modest relic, with rich history as a strategic fort through multiple eras.

This Castilian castle has stood the test of time like few others.

This sandstone marvel of nature is worth a stop along Highway 65.

Sometimes called the “Little Golden Gate," this bright yellow structure is the last driveable suspension bridge in Arkansas.

The predecessor to this bridge was depicted in a famous Japanese woodcut print that influenced Van Gogh.

These medieval wooden bridge pillars appeared out of nowhere in the aftermath of a huge earthquake.

These remnants of Old London Bridge possess unique acoustics that allow for whispered conversations to carry from one side to the other.

This unassuming bridge is most likely one of Michelangelo's unfinished masterworks.