This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

This hanging crocodile is thought to be the "dragon" that once plagued a Czech city.

A peculiar clock commemorates a historic victory won by ringing the noonday bell an hour early.

A surreal statue honoring Prague's favorite literary son.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Two stunning 17th-century libraries and a cabinet of curiosities.

A collection of Lenin busts and other Soviet Era statues sit idly behind the Semipalatinsk Hotel.

The busy transport hub is home to the tallest airport slide in the world.

The highest pedestrian bridge in Singapore looks like a series of undulating waves rising between two public parks.

One of the few working locomotive roundhouses in the United States.

This lighthouse and shipwreck museum keep a torch burning for the memory of the SS Edmund Fitzgerald.

The most southern point you can drive to in the Western Hemisphere.

Built on the remains of one the Incas’ most important gathering spots, this square keeps the spirit of a fallen empire alive.

Situated on a sacred Inca site, this 16th-century cathedral took nearly 100 years to build.

This geometric feat is a testament to the Incas' mesmerizing architectural abilities.

Visiting dignitaries and Hollywood stars once stayed at this 1920s hotel, alongside ghosts that are said to haunt its corridors.

An ancient Incan convent on Lake Titicaca's Island of the Moon.

This mysterious complex of abandoned yurts and fading murals was meant to be a center of science and spirituality in Kyrgyzstan.

Time capsule of a museum, in which the Soviet Union remains alive and kicking.

Extremely isolated Silk Road caravanserai in the middle of nowhere.

This sprawling market is a one-stop shop for traditional Kazakh foods, from mare’s milk to sheep’s head.

At 72 feet below sea level, it's the lowest commercial airport in the world.

This Soviet statue is based on a piece of propaganda that's been elevated to national myth.

This Soviet-era athletic and recreation facility is the highest ice skating rink in the world.