The Bristol Camera Obscura housed in an ancient windmill.

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

This tangled English forest looks like something right out of a fairytale.

This painted wooden sculpture depicts the characters of a popular Devon folk song.

One could not be blamed for literally walking all over this supposed landmark.

The castle still holds traces of the abandoned Roman fort it was built atop.

Regency-era excess on the English Coast.

The hallucinogenic center of the ancient world.

The ruins of an abandoned medieval city where the last Byzantine emperor was crowned.

Step inside an ancient beehive tomb built for a mysterious cult hero.

This legendary city has been a tourist attraction for centuries.

A 2,000-year-old computer demonstrates remarkable engineering and astronomical precision.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

Legend says this sacred tree was a gift from goddess Athena.

Heralded as the world's first theater, these ruins are often overlooked as they reside in the shadows of the Acropolis.

This mystical orb covered in strange symbols is thought to have been used in ancient Greek magical rituals.

The walls of Germany's Parliament still show the scars of the Red Army takeover in World War II.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

A memorial in the Tiergarten is a reminder of the suffering inflicted on homosexuals by the Nazi regime.

The site of the famous Nazi book burning campaign of 1933 remembers its "Night of Shame".

A fascinating insight into daily life in the Eastern Bloc.

The only visible remains of this ancient Greek underground temple is its roof protruding from the earth.

Also known as the Temple of Poseidon, this is one of the best-preserved Greek temples in the world.

For centuries, this large Roman villa remained hidden thanks to the eruption that buried nearby Pompeii and Herculaneum.