The oldest residential street in Europe also features an optical illusion.

This research hub in the Amazon Rainforest is perched amid one of the world's most biologically diverse landscapes.

The most remote tree in the world is more than 170 miles from its nearest neighbor.

The hidden "ballroom" under a mansion lake was built by a criminal who ate a cyanide pill during his trial.

The sixth of London's "Magnificent Seven" cemeteries, and a source of unlikely inspiration to Beatrix Potter.

According to legend, this tomb holds the secrets to time travel.

Meant to resemble a massive tree, the building is the best example of Spanish organicist architecture in Madrid.

An exercise in radical design and social living that became the epicenter of Soviet spy networks in London.

This sculptural piece by the artist Tom Otterness doubles as a jungle gym.

The world's only teal arches exist in a city that cares more about its aesthetic than an Instagram influencer.

This overlooked street light once served as a KGB dead letter box.

The story behind this beloved toy—named for Theodore Roosevelt and owned by his grandson—is more complicated than you might guess.

A computer bug so primitive it was an actual insect.

The middle finger of modernity.

These grandstands are among the oldest continuously used stands in the world.

The story behind this uniquely-shaped tower involves ancient empires, local legends, and new words.

It holds a fabulously designed tribute to astronomer Edmond Halley.

This local mascot has been a presence in the area since the 1960s.

An ode to the famous Las Vegas signage.

An impressive armored bronze effigy marks the tomb of one of the medieval era's greatest warriors.

Today, Kent's medieval monarchs hold court on a busy pedestrian thoroughfare—or at least their statues do.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

The only statue ever crafted by award-winning animator Ray Harryhausen.

This pole near the infield rail at Belmont Park marks the jaw-dropping margin of Secretariat’s 1973 Belmont Stakes victory.