The only urban monument in the world designed by the great surrealist painter Salvador Dalí.

Commonly acknowledged as the only public monument to the Devil himself.

An apparition of Virgin Mary in Herzegovina.

The medieval ferry service has been going strong since the 14th century.

An ancient knight and a symbol of the city's freedom.

These abundant, over-the-top monuments are so widely scattered that they define the entire compact capital cityscape, often leading to jokes about whether there are more statues than residents.

One of Mexico's youngest major cities still holds on to this structure representing its short modern history.

At least seven hues of blue and turquoise make this freshwater lagoon unique.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

This monument is a stark reminder of the horrors of the Zanzibar slave trade.

This unique building in the main square stands out among the city's typically Baroque architecture.

This building has two facades of clashing architectural designs.

Underneath this Byzantinian church lies a necropolis filled with ancient tombs and the ruins of previous churches.

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

A fire once nearly devoured this gorgeous 14th-century Gothic cathedral.

This snug medieval lane is one of the narrowest streets in the world.

The European towns of Brașov and Râșnov each have proud signs reminiscent of the Hollywood sign.

A hidden treasure of an abandoned city lies deep in the jungles of Campeche, Mexico.

Clap your hands at the base of the pyramid, and the song of a sacred Mayan bird will echo through the air.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

Every equinox this Maya pyramid puts on a spooky ancient light show.

Its sunny hues are believed to have inspired the town's color palette.

This small, yet notable, cable-stayed bridge was built to support tourism to a series of internet-famous pink lakes.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.