Home to the largest urban bat colony in North America, estimated at 1.5 million bats.

This Italian stadium makes liberal use of fascist statuary to evoke classical sporting arenas.

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

An inclusive, climate-resilient playground honors the life of a young Boston Marathon bombing victim.

A former waterfront market is now in the center of town due to some interesting Boston engineering.

An 11th-century runestone decorates the halls of Terminal 2 of this Scandinavian travel hub.

This giant subway sculpture celebrates the fruit that inspired the theory of gravity.

Stockholm's narrowest alley is barely over two feet wide.

Stockholm's deepest subway station is also a stunning ecological wonder.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

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

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.

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

Macabre astrological automaton clock dating to the late 1400s.

The world’s largest street art museum.

Yo, Adrian!

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

A spherical "micro-nation" in the heart of Vienna.

Western Australia’s heavenly staircase is not for the faint of heart.

The longest timber-piled jetty in the world has an underwater observatory.

It's beautiful, it's haunted and its claim to fame is that it's the oldest existing stone arch bridge in Australia.

This Western Australian mint was established during the height of the Australian gold rush.

More than 100 colorful residents stand post in this seaside Australian city.

You can climb to the top of the world's largest rocking horse.