The oldest residential street in Europe also features an optical illusion.

This enormous secondhand bookstore inside a Victorian train station sparked the "Keep Calm and Carry On" craze.

This Victorian gate contains cryptic inscriptions in Greek, Latin, and Hebrew.

Amidst towering office buildings, a local pub lives inside Sheffield’s oldest surviving domestic building.

This magnificent mural was created with over 30,000 colored bricks.

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

This restored Portuguese cafe may well be the most beautiful place in the world to grab a Big Mac.

Sip cherry liqueur at a bar dating back to 1840.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

This charming candle shop has been in business since 1789.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

A rare example of the RAF’s flying spy taxi.

One of the last remnants of the Bessemer process that revolutionized steel production during the industrial age.

This Sheffield sculpture composed of 17,000 Allen keys honors both urban falcons and a furniture icon.

The biggest and deepest Cold War bunker open to the public can be found in southeast England.

This foreboding medieval castle was twice besieged by barons rebelling against the English king.

This skewed English house has looked like it's going to fall over for centuries.

An anti-tank graveyard in the English countryside.

England's most notorious suicide spot.

These stark white cliffs were spat up by the sea and are slowly being retaken by it.

This former sewage pumping station is now a fascinating museum.