The ruins of this gorgeous clifftop castle look like something from a fantasy novel.

This 17th-century street hidden beneath Edinburgh was once a breeding ground for the black death.

The burial ground of two kings and a queen is now a calm city park in the middle of bustling Seoul.

An abandoned, rusty old relic of railroad history stands at attention over the Cuyahoga River.

An Irish Memorial commemorating those who perished due to potato blight.

This staircase in a lush tropical grotto was built by enslaved laborers and renamed to honor Queen Victoria's role in ending slavery in the British Empire.

Near the former site of numerous witch burnings, this lavish Edinburgh mainstay pays homage to Scotland's brutal history.

Now home to a drinking establishment, this building has a macabre history.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

Come for the oysters, stay for the priceless art honoring inventors across history and Scotland's favorite outdoor sports.

This historic pub has maintained much of its 1906 decor, including a small sequestered room for women, where orders were slipped through a tiny window.

A 300-year-old tea shop that brought tea to the English people, not to mention the Queen herself.

Giant novelty guitars now mark the spot where Robert Johnson is said to have sold his soul to the devil.

A decaying concrete oil tanker served as a disposal location for bootleg hootch.

This tiny, hurricane-resistant house in Galveston is one of the city's most notable architectural oddities.

Legend says if you stick your thumb in the hole and it gets wet, your wish will be granted.

A small etching on the white marble parapet was written in runic script by a Viking mercenary.

Eat your Big Mac in a DC-3.

One of the steepest streets in the United States makes an intriguing challenge for cyclists.

Along this wire fence, travelers have been leaving a particular memento since 2012.

Iceland's tribute to its thankless civil servants.

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

Fragments of a massive unfinished sculpture sit near the main quad of the University of Illinois.

This conservation area is also home to many of the region's desert tortoises.