This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

This hidden art nouveau gem was designed by an architect in search of a national style.

A Trabant car, a kangaroo statue, and a plethora of plants take over this abandoned-factory-turned-bar.

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

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

Paris' linguistic guide to the international language of, yes, love.

This sweet-toothed bear searching for snacks has been a symbol of Madrid for decades.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

This bone-filled cave got its name after they found 140 bear skeletons inside.

Overshadowed by other, more famous Maltese catacombs, this ancient burial chamber has one of the best examples of a ritual agape table.

One of the most photographed locations in the entire city.

This former mill comes to life during the Christmas season.

Τhis feline monument commemorates fallen soldiers on a field that saw many, many battles.

Dedicated to the god Dionysus, this theatre was used for both musical and theatrical performances.

A gorgeous example of 13th-century Gothic architecture.

This medieval castle was reconstructed by Carlo Scarpa.

A whale rib was used to advertise the store by the arch that offered exotic goods from far away.