The most visited, and possibly most controversial, museum in Germany.

This historic floating crane became an unlikely symbol of the port of Trieste.

The world's most active stratovolcano is almost always erupting.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

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

Designed as a reminder of one of the darkest moments in Austrian history.

The beautiful baroque library of the Hapsburg empire.

In the middle of a Vienna square, Roman ruins dating back some 2,000 years are on display.

Handsomely crafted representations of our round planet.

A mechanical clock built in 1914, with a rotation of 12 historical figures on its face.

Legends surround an ancient tree trunk riddled with nails for good luck.

The crypt of the imposing Stephensdom holds royal intestines and thousands of skeletons.

Along the edge of this fountain are 365 smaller fountains that represent the days of the year.

Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.

Vienna's diversity-themed traffic lights were inspired by the Eurovision Song Contest.

A set of outdoor stairs named in honor of a famous Austrian artist.

This former insane asylum now holds a pathological anatomy museum.

This museum promotes informed contraception by documenting its often secret past.

An ornate private entrance to the Vienna subway built specifically for the emperor.

The first modernist church in Europe.

The housing complex served as an anti-fascist fortress during the Austrian Civil War.

Giant WWII fortresses that fired 8,000 rounds a minute, now home to thousands of pigeons.

Op-art architecture designed for happiness.

More than a millennium's worth of municipal records preserve the political history of Austria.