This natural sea arch highlights Ireland's rugged coastal beauty.

A tribute to the incredible generosity the Choctaw Nation showed the Irish people during the Great Famine.

This controversial Irish show cave is home to a massive formation known as the Great Stalactite.

The oldest pub in Ireland may also be the oldest surviving bar in the entire world.

Perfectly preserved ancient monastery in an impossibly dramatic location on a rocky island in the Atlantic.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

A market built atop boats is one of the few floating holiday markets in Europe.

This massive mural by famed pop-artist Keith Haring was hidden for almost 30 years until its 2018 rediscovery.

The Bloemen Route, or “Flower Route”, stretches 25 miles through prime Dutch tulip country as a result of “tulip mania,” the world’s first economic bubble.

This unusual elevator doesn’t stop or slow down.

Three connected pink triangles memorialize persecuted gays and lesbians throughout history.

Sail in for a ’dam good slice.

Peek through a transparent pyramid and drink in the mountain made of books.

Famed for its pie, this eatery has a hidden tunnel that allowed Catholics to secretly walk to church during the Reformation.

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

A silly medieval mural preserved on the side of a Viennese house.

The topiary maze at the Habsburg hunting lodge.

How did an Australian statue of the Bard of Avon end up in the Hungarian capital?

A much-loved sculpture depicting the hero of a 1956 anti-Soviet uprising.

A scene from one of Hungary's most famous novels.

A giant glider—designed by the father of the Rubik's Cube's designer—now soars within a shopping mall.

The largest statue of this convex, homogeneous object with just one stable and one unstable equilibrium point.

A diminutive statue that was inspired by the sculptor's own daughter.

A relic of World War I that now exist as a piece of public art.