This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

Pilgrimage site for star-crossed lovers.

Invented in the mid-19th century, this machine could send copied images via telegraph lines.

The mental institution where Van Gogh created some of his most famous work now allows guests to walk in the artist's footsteps.

At Monet's beloved home you can still see the Japanese bridge, waterlilies, and weeping willows that were the subjects of some of his most iconic paintings.

This tea house was a hand-built gift from Boulder's sister city in Tajikstan.

This modern antique shop is a museum for 1980's Saturday morning cartoon culture.

An innovative local park built from an abandoned sewage treatment plant.

This sidewalk tribute honors Colorado's great culinary creation.

The oldest continuously operating fish market in the United States.

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

The prototype for all Nazi concentration camps.

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

This World War II bunker now survives as a documentation of the Nazi regime and war crimes.

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

A slice of central Asia in the middle of Berlin.

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

During World War II, the Nazis repurposed this beer cellar to store stolen artwork.

A castle from the Holy Roman Empire that hosts traveling youth... in its stables.

A sprawling Baroque park with 300-year-old hydro-pneumatic waterworks.

A tribute to the Polish insurgents who fought in the failed attempt to end their city's Nazi occupation.

A hidden art gallery in an abandoned Warsaw fort.

Budapest's Communist-era statues, banished to the suburbs.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.