This beloved ancient tree is the pride of this city center.

A well-restored ancient archaeology site gives a real feel for life during the Roman age.

This 47-story "M" needed 20 years to be completed

The magnificent sanctuary is Spain's first purpose-built structure of its kind.

This exhibition space designed to look like the skeleton of a whale is hidden underground.

If you like Art Deco you will love this bridge.

Where once there was a train station bathroom, there is now this German burger joint.

Explore this medieval cathedral by trying to spot all the malevolent monsters hiding in its beautifully colored windows.

There has been an astronomical clock on this spot since the 14th century.

Two geological phenomena in one precarious locale: a towering stone window, and a deep blue void.

The fishing boats that moor in this small lagoon enter and leave through a tunnel to the sea.

This almost-forgotten underground dungeon housed several convicts over the years, including Caravaggio.

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

A centuries-old forgotten underworld lies beneath Malta.

This spectacular dome managed to survive after being bombed in World War II, in an event known as the "Miracle of Mosta."

Burial grounds for more than 1,000 bodies deep under the modern town of Rabat.

This building’s ghostly exterior reflects its former lives as a prison, school, and funeral home.

Over 2,000 ancient temples dot the Myanmar landscape at the site of this famed archaeological site.

The floor of this spectacular Baroque sanctuary is covered in memento mori.

Overshadowed by other, more famous Maltese catacombs, this ancient burial chamber has one of the best examples of a ritual agape table.

A hidden tunnel of bones in one of Malta's oldest churches.

A trough of 700 strange bronze faces runs through a narrow alley in Ljubljana's old town.

These crumbling towers are some of the last remnants of a centuries-old Vietnamese culture.

A nightmare for the claustrophobic lies hidden in Southeast Asia.