A network of underground water channels that dates back to the Middle Ages.

Famous landmarks and structures from across Italy fill this miniature park.

Water and windows define this defensive Italian well.

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

An alchemist's "magic door" stands in the middle of a Roman park.

The yawning maw of this pagan visage is said to bite off the hands of liars.

This statue of a falling man commemorates a teenage martyr of the Hungarian Revolution.

A tropical paradise just a short trip from the opera house is filled with beautiful winged creatures.

An islet filled with wooden houses where the open sea meets a lagoon.

This slumbering beast honors the Bavarian soldiers who died in Greece during a 19th-century typhoid outbreak.

A glimpse into the festive and private lives of medieval Europe.

The monument honors the first (and for a long time, only) African-born philosopher to teach at a German university.

A staggering collection of satellite models and actual flight parts.

An exquisite panometer representing Dresden as it was from 1695 to 1760.

This museum tells the story of lake dwellers from 4000 BC to 850 BC, replete with stilt houses and goats.

The world's first clock to use set theory as a measure of time required the invention of a new light bulb just to maintain its obtuse measurements.

The site of the famous Nazi book burning campaign of 1933 remembers its "Night of Shame".

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.

This innocuous-looking button may have been used to assassinate a king.

This Belgian palace was long the domain of priests and aristocrats but is now being turned into an art commune.

Cozy basement bar sports an inventory of over 2,000 beers.

Once the hottest nightclub in France, Amnesia now lies in ruins after a 2000 bombing.

This mountaintop mariner’s church is packed with model ships and nautical art while hosting an annual maritime festivity for the townsfolk below.

An art-filled botanical garden and former dyeworks hiding in plain sight.