Hidden within a Netherlands crater is a stone bed that lets those who lie in it see the sky as a curved surface.

Built by crowdsourcing, this wooden foot bridge saved a part of Rotterdam that was languishing in wait of city funding.

A church of bones, decorated with 40,000 human skeletons.

This former quarry is now a picturesque gorge that hides a sunken lake.

Microscopic scenes; some call it novelty, some call it art.

Two stunning 17th-century libraries and a cabinet of curiosities.

Increasingly decayed figures stand as a powerful reminder of the human costs of Czech Communism.

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.

Steadily reminding Czechia of its past.

This automated sculpture of two men peeing will spell out text messages with their micturition.

Macabre astrological automaton clock dating to the late 1400s.

A 400-year-old mummified arm dangles from the ceiling of St. James the Greater, serving as a warning to thieves.

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

This Prague museum collects brutalist relics and memories from the country's former Soviet rule.

A mocking tribute to the past and modern leadership of Prague.

The bunker where Hitler took his own life is hidden under this deliberately ordinary parking lot.

Italian poet Dante Alighieri is entombed in this small mausoleum in Ravenna, and his hometown of Florence has never been too happy about it.