Sacred Indian temple that’s all monkey business.

More than half of this Indian palace is drowned but it looks all the more spectacular for it.

The 953 windows undoubtedly make this the world's most beautiful screened porch.

One of Amsterdam's narrowest houses is located right across the canal from its widest.

This unattributed sculpture in Amsterdam is hiding in plain sight.

Seven mini rowhouses fill the gap between 54 and 70 Westerstraat.

The history and future of cannabis.

A copy of the famous statue can be found in this Florence piazza, along with one of the most breathtaking views of the city below.

A slightly creepy gallery of plaster cast models in the same museum as Michelangelo's David.

This strange bovine gargoyle is said to have been put in as a passive aggressive form of revenge.

Secret refuge and museum of the Duke of Florence.

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.

The doodles of a genius line the walls of a secret room under the Medici Chapel, where they were hidden for nearly 500 years.

A large grotto built in the 16th century amidst Florence's famous Boboli gardens.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

An alchemist's "magic door" stands in the middle of a Roman park.

This demon atop the Notre-Dame de Paris looks utterly bored.

A 16th-century fountain marks the site of a lost medieval cemetery once filled with mass graves.

Original cabaret handbills, posters, and feline artwork are a purrfect highlight of the Museum of Montmartre.

This statue was given to France by the United States to commemorate the centennial of the French Revolution.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

Most of Britain's gold reserve was secretly stashed here after the start of World War II.

The tower was originally used as a chimney for the waste incinerator of St. John's Precinct and Market.

Charles Dickens described the concert room in this amazing Victorian hall as "the most perfect room in the world."