Hidden in a grotto 26 feet below Nottingham's oldest hotel, this stylish subterranean drinking den is notoriously hard to find.

This coffee shop lies hidden beneath a historic church.

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

The broken skateboards that became a poignant memorial to a murdered skater.

It's believed a castle existed at this site since the 12th century.

A kaleidoscopic warehouse-maze of handmade neon signs.

A sweet symbol marks the place where torturous executions were once carried out.

Touching this 18th-century Scottish philosopher’s toe allegedly conjures good fortune.

A quartet of brightly colored mythical beasts stand sentry at this gateway.

This cannonball embedded in the side of an Edinburgh house once served a surprisingly pedestrian purpose.

A rare and unique example of an 18th-century door latch calls this restaurant home.

A public art piece that barely gets recognized, but then that might be the point.

A former telephone box found new life as a photo booth and charity fundraiser.

An iconic red telephone box turned tiny art gallery.

Neon artworks light up this dark Edinburgh tunnel.

A pair of stones embedded in an Edinburgh street memorialize one of the city's last public hangings.

This former train tunnel is filled with lines from a poem crafted by Robert Louis Stevenson.

This alley off Edinburgh's Royal Mile contains remnants of the city's seedier history.

An American ghost town hides along a side street in Scotland's capital.

This obscure walkway links Edinburgh’s Old Town with one of the city's prime vantage points.

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 remnant of the original World Trade Center complex continues to serve as a commuter gateway.

Those belting out show tunes might not realize this piano bar marks the site where Thomas Paine died in 1809.

Fake subway tiles were installed to cover a design that resembled the Confederate flag—it's unclear if the resemblance was intentional.