The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

A unique look into the bowels of a century-old funicular.

Visitors may notice something strange walking through this quaint German town.

A six-story, asymmetrical tower filled to the brim with scientific experiments.

A former customs station on the border of Germany and the Netherlands.

Largest illuminated advertisement sign in the world.

This red London phone booth once stood in front of Buckingham Palace and was used by the queen.

A collection of 4,000 thimbles that's more versatile than one might imagine.

This public observatory is home to the "celestial cannon," the longest pointable telescope in the world.

Whimsical wash tubs row down the stream as part of this Carnival celebration.

This famed marionette theater and museum is bursting with imaginative string puppets.

A century-long search for a church that was never there.

The highest cold-water geyser in the world.

The Suurhusen church tower in Germany leans over farther than the famous Leaning Tower of Pisa.

1898 German railroad depot museum with working engines, steam train excursions, and hands-on displays.

This monument to those fallen in the World Wars is accompanied by a U-boat that Germany bought for a Deutsche Mark.

A tilted half-timbered house from 1672 is built into a salvaged segment of a medieval wall.

A unique bridge with an equally unique view.

A steam powered train that runs on city streets.

This peculiar museum offers hands-on interaction with seemingly intangible principles of mathematics.

According to a satirical conspiracy theory that persists today, this German city of 300,000 is a hoax invented by the CIA.

This futuristic German television spire is actually the world's largest digital clock.

The only remaining U-boat that is still floating never actually saw any action in World War II.

Nestled on the banks of a river in Nuremberg is a small museum that was once home of the city's official executioner.