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

Valletta’s outdoor theatre stands within the ruins of a 19th-century opera house.

So opulent and massive it was once dubbed a palace, this hotel's doors closed temporarily in 2007 and failed to reopen.

Malta’s largest cemetery is a Victorian-era architectural masterpiece.

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

The people of Padua pledged to construct this church if the city was spared from destruction during World War I.

This macabre masterpiece of a mural is one of Francisco Goya's "Black Paintings."

For decades, Puerta del Sol has been illuminated by a giant, guitar-wielding bottle of sherry.

The remains of a convent turned military barrack in the heart of Madrid.

An ancient Egyptian temple in the middle of Madrid, Spain.

After the queen of Spain had a dream where these statues fell and crushed her, they were removed from the palace and given new homes around Madrid.

A small but stubborn relic of Spain’s turbulent past hides in plain sight.

A rare set of strings by famed instrument maker Antonio Stradivarius is on display in the Royal Palace.

This abandoned viewing platform has become a monument to unnecessary government spending.

A curious fountain that resembles a beloved character from the 1960s.

Of the many chalices in the running for the Holy Grail, this one in Valencia Cathedral sure looks the part.

With a facade that measures just 107 centimeters, this five-story building is one of the skinniest in Europe.

This amazing example of Valencian Art Nouveau looks more like a cathedral than a public market.

When a massive landslide hit one of the world's tallest dams it created a tragic environmental disaster.

An open-air museum in a mountain valley features works designed to blend in with—and disintegrate back into—their natural surroundings.

This Italian foot path winds through the mountains via 52 individual tunnels.

The remains of 50,000 World War I soldiers rest under a towering arch overlooking the Alpine battlefields.

The 1940s structure houses what was once Europe's largest telescope.

A modest museum in the final home of Italian poet and father of modern Italian, Francesco Petrarca.