A subterranean house of worship carved right out of the bedrock.

A golden plaque marks the site of the mysterious unsolved assassination of the former Swedish prime minister.

Stockholm's tiniest statue is of a small boy looking at the Moon.

The world's first invisible city square is an homage to a man who pushed the boundaries of art.

Disused seaplane hangar gets a second life as the jaw-dropping home of Estonia's museum of maritime history.

Thousands of miniature bronze sculptures have taken over this city square creating a unique art installation.

This floating sculpture of ice is a poignant reminder of nature's power.

The design of this beautifully crafted building was inspired by Norwegian glaciers.

One man's exploration of the human form, including the bizarre and delightful "Man Attacked by Babies."

Thanks to a spelling mistake this bizarre beaver-tiger hybrid became the symbol of a Siberian town.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

An ossuary built in 1210 to collect bones from the Ospedale Maggiore of Milan.

The mummified relic of St. Catherine sits forever on a golden throne.

A small window on Via Piella offers a lovely and rare peek at Bologna's lost canals.

Over 100 towers were built in Bologna during the Middle Ages, but only 22 survive.

Legend has it this fountain built to symbolize the Pope’s power hides a strange secret concerning Neptune's manliness.

A striking memorial recalls thousands of Bolognese men and women killed fighting fascists in World War II.

The tomb of the mythological founder of Padua is not hidden in some obscure crypt, but stands right in the middle of the city square.

This old medieval prison tower has been a site of astronomical research for more than 250 years.

Something's missing between the arcades of the Palazzo della Ragione in "the city of the three withouts."

The incorrupt tongue of the patron saint of lost things is venerated in this basilica.

The oldest botanical garden in the world that technically isn't the oldest.

One of the world's oldest working clocks is curiously missing the Zodiac sign of Libra.

A whale rib was used to advertise the store by the arch that offered exotic goods from far away.