This inexpensive lodging house was once a prison notorious for its inhumane practices.

This series of underground chambers contains Europe's largest subterranean lake that is slowly drained each day.

A statue in the heart of Edinburgh honors a bear that served in the Polish military during World War II.

Used as an example in one of the first dictionary entries for "museum" in 1706.

This permanent collection of preserved bodies taken from Irish bogs is one of the leading authorities on such morbid mummies.

This gracefully curving formation looks like a massive wave that was suddenly turned to stone.

Op-art architecture designed for happiness.

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

This massive collection of British military artifacts includes the heartbreaking personal letters of the men in the trenches of WWI.

A 26-foot shark sculpture—a statement about bombs—set off a municipal battle royale.

Site of the 1889 murder-suicide of crown prince Rudolf and his lover Mary Vetsera.

The largest stone circle in the world has ended up bringing up more questions than it has answered.

Famously misunderstood wonder of the ancient world

The glowing blue Nymphaeum of Emperor Tiberius.

This massive mall has hundreds of shops, an amusement park, and a history of deadly amusement attractions.

This Arctic storage facility is a secure backup for agricultural biodiversity.

A fantastic castle rumored to be the birthplace of King Arthur.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

A pixel art killer whale is frozen mid-leap in this Vancouver square.

This legendary city has been a tourist attraction for centuries.

A theatre built to house the rowdy Oxford graduation ceremonies became the stage for a debate about God's existence.

This short bridge is the only thing connecting a tiny Irish island to the mainland.

The modern birthplace of Irish freedom.

Charnel house at the foot of Mount Sinai.