A young Gustave Eiffel assisted in the construction of this skinny metal observation tower.

Bordered by forest on three sides and the ocean on the other, the Great Dune of Pilat is the highest sand dune in Europe.

The world's largest reflecting pool is just two centimeters deep.

For those late-night mollusk cravings.

A melancholy jester sits on the grave of a famous 20th-century ballet dancer and choreographer.

These murals stand as reminders to the troubled history of this Northern Ireland city.

This Victorian-era public house has set the standard for pub-style elegance for over a hundred years.

These barriers stand as stark reminders of Northern Ireland's troubled past.

Belfast's namesake river still winds below the city center, hidden from sight.

A small plaque highlights the damage caused by German air raids during World War II.

Stroll through Welsh history in a village of reconstructed structures.

The castle still holds traces of the abandoned Roman fort it was built atop.

A harem-inspired Moorish fantasy design in a Victorian-era Welsh castle.

This pedestrian walkway cuts through a cemetery and over several burial vaults.

In 1977, an eccentric book lover formed a micronation for book lovers.

This massive monument has been telling the time for 150 years—at a slight angle.

Go deep down into the earth to experience the world of Welsh coal miners.

Gladiators once walked this ancient, subterranean passage.

An icon of the Battle of Britain is frozen in flight in a grand Victorian museum.

A 19th-century Neoclassical building now housing a Hindu temple represents modern-day Glasgow at its most multicultural.

Inside this art museum resides one of Glasgow's most famous musical instruments.

This museum offers a glimpse into early 20th-century Glasgow life.

This extinct volcano rises above Edinburgh and is special for its panoramic views over the city.

This statue stands as a message against the ills of Apartheid.