Eighty million natural history specimens call this gargantuan museum home.

The curios of pharmacist and collector Henry Wellcome.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

One part local history, 99 parts gruesome haunted house.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

A detailed pachyderm supports Rome's smallest Egyptian obelisk.

Charles Dickens was not a fan of the ghastly wall dressings in this 6th century church.

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

The yawning maw of this pagan visage is said to bite off the hands of liars.

The burial place of an obscure North African saint was turned into a macabre body preservation factory for the 17th-century Neapolitan elite.

An underground paleo-Christian burial site composed of the remains of several cemeteries and Basilicas.

A labyrinth of ancient tunnels hidden below the city holds the ruins of 2,500 years of history.

The once forbidden "secret cabinet" of erotic art from excavations of Pompeii and Herculaneum.

Sofia's legislative center is continuously reinventing itself.

A vast Communist-era exhibition space in the Bulgarian capital.

"Holy Wisdom" overlooks the city that became its namesake.

A gigantic statue of a Russian soldier watches over the ancient city of Plovdiv, a prominent reminder of the Soviet period in Bulgaria.

"Unity, Creativity, Beauty."

This ancient theater, restored in the 20th century, lives on as a venue for dramatic and musical performances.

A striking symbol of the Bulgarian capital.

A collection of art from Bulgaria's time as a communist state.

This historic black and white monastery is one of Bulgaria's architectural jewels.

A Bulgarian monument to Russia's role in World War II is constantly being painted in pop culture protest.

This memorial to the victims of the Romanian Revolution of 1989 is often compared to a potato on a skewer.