An ancient Roman temple first dedicated to an emperor's wife is now a church.

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

This curious, round temple is the oldest still-standing marble building in Rome.

The only remaining arch of the oldest stone bridge in Rome stands in the middle of the Tiber.

The "Great Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

Rome’s legendary peephole vista is also a former Crusader stronghold.

This hill made entirely of ancient Roman jars was simply a garbage dump to the people of the time.

"Leave a He-Man, Take a Transformer" and share a story about your real-life superhero.

This fountain is dedicated to the workers who perished constructing the Fréjus Rail Tunnel.

An enormous playhouse designed to look like 21 stacked Lego bricks, with another 25 million colorful Legos inside.

The original home of the Lego has a huge amusement park dedicated to the iconic plastic toy.

Beneath Denmark's Højbro bridge, a bronze merman and his seven sons forever mourn for the mother and wife who left them for land.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

Copenhagen's celebrated theme park and gardens.

One of the most enjoyable bits of history at Coney Island and “the most romantic ride in the world.”

With only one flight in and out a week, the unfenced runway at this small island's airport transforms into a seaside park for locals and visitors.

This legendary urban waterfall creates a dazzling display of rainbows.

New York City's only radical feminist independent bookstore.

A reminder to choose water over wine since 1888.

For almost a century, this East Village newsstand has served egg creams to beats, hippies, punks, and everything in between.

The 28-foot granite map plots the locations of 40 theaters in New York City.

Slyly buy a shake in the Parker Meridien lobby.

This castle-like building in Manhattan helped destigmatize cancer in the 19th century.

This hidden library of physiological ephemera contains centuries worth of knowledge on the vim and viscera of the human body.