This ancient Roman arch misled treasure hunters for centuries.

Remnants of a 4th-century church with vivid medieval frescoes and ancient sarcophagi hide beneath this old basilica.

The "Greatest Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

A treasure trove of Renaissance-era funerary art in a Roman church built on top of Nero's grave.

An architectural oddity hides in plain sight on this iconic London bridge.

The barrel-made lookout from Shackleton's final ship is tucked away in the crypt of one of London's oldest churches.

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

A mysterious shape catches the eye in this 16th-century painting.

The sumptuous ceiling was one of the last things Charles I saw before his execution.

A statue of the legendary Celtic warrior queen who fought the Roman invaders stands in one of the cities she once destroyed.

This intricately carved and hilariously huge bed was such a famous symbol both Shakespeare and Byron used it in their writing.

A tribute to an explorer and naturalist often overlooked by history.

The monster at the center of the Darwin Center Spirit Collection.

Eighty million natural history specimens call this gargantuan museum home.

The famous polar explorer stands outside the Royal Geographical Society's headquarters.

The names Lúthien and Beren can be found inscribed on the shared grave of the famous writer and his beloved wife and muse.

The oldest working mechanical clock in the world.

The first archaeological site discovered by aerial photography.

Famously misunderstood wonder of the ancient world

Ancient human remains unearthed around the iconic monument.

This picturesque horseshoe weir was first built in the 1600s to prevent flooding in the town of Bath.

The "father of immunology" used this humble hut to offer the local people some of the world's first free vaccinations.