A daily replay of the experiment that proved the rotation of the Earth.

Current docking place of the SS United States, the fastest transatlantic ocean liner.

This elaborate towering structure was once famed for its revolutionary height.

Ant sculptures march up the side of what used to be an iconic spot in punk rock lore.

Yo, Adrian!

A clone-tree in Washington Square Park sprung from seeds that went to the Moon and back.

Dr Barnes' $25 billion private collection of art and arboretum.

The origin of this mechanical boy was a mystery until he revealed his maker by writing it in perfect cursive.

Mural made of 100,000 pieces of hand blown glass, and until recently, the largest glass mural in the US.

This charming colonial alleyway is one of the oldest continuously used residential streets in the U.S.

Philadelphia boasts one of the best — and most often overlooked — traditional Japanese gardens in North America.

A layered tribute to the work of mosaicist Isaiah Zagar.

World's first "penitentiary," meant to be humane, drove men insane.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

Once the home of a hermetic monk, this cave now houses a small church.

A church of bones, decorated with 40,000 human skeletons.

An enormous and lavish Gothic church in Czechia.

Steadily reminding Czechia of its past.

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.

This walkway is so narrow it needs its own light to stop pedestrian traffic jams.

Increasingly decayed figures stand as a powerful reminder of the human costs of Czech Communism.

A series of playful yellow penguins share a serious message about the environment.

This spooky statue sits outside a famous Prague theater.

What looks like a suicide in progress is actually a statue of Sigmund Freud.