Where commuters walk through remnants of an ancient Greek necropolis.

This small 16th-century church in Athens is almost entirely surrounded by a modern building.

The railway carts travelers to central Athens's highest peak, which offers stunning vistas of the city.

The Cycladic architecture makes this Athens neighborhood feel like an island paradise hidden in the shadow of the Acropolis.

An ancient octagonal weather station named for the eight Greek gods of wind.

A public urinal so pretty, it was declared a national monument.

One of many reminders of Tesla's scientific contributions overlooks the falls which inspired him.

This former sewage pumping station is now a fascinating museum.

A remarkable feat of Victorian engineering across the Firth of Forth.

This unassuming alcove in London’s famous Tower Bridge once served to capture, store, and display dead bodies from the River Thames.

A roadway designed for a visiting monarch.

A giant roundabout made up of six smaller roundabouts can befuddle the uninitiated.

The beloved beast's taxidermy remains sit in the Natural History Museum's cafe.

The charming collection illustrates life in Lincolnshire in the 18th through 20th centuries.

All unmarked mute swans on the Thames are owned by the Queen per a tradition that began in the 12th century.

Also known as Rye Castle, this 13th-century fortification later became a prison and held one of Rye's most famous criminals.

World's largest working waterwheel has been around for over 150 years.

This charming, narrow-gauge railway in the Thames Estuary is sometimes referred to as the "Train to Nowhere."

A living memorial to the trees London lost during the Great Storm of 1987.

The bronze uniforms commemorate the vital role of women during World War II.

Legend says these colorful, invasive residents are the descendants of birds released by Jimi Hendrix.

These picturesque ruins crumble beautifully into the ocean.

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

Home to Alan Turing, the cracking of the Enigma code, and Captain Ridley's shooting party.