A 12th-century fortress containing some of Berlin's oldest buildings.

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

A tree-like building perches on its trunk in the Steglitz neighborhood of Berlin.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

Berlin's natural history museum houses the world's largest mounted dinosaur and the late beloved polar bear Knut.

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

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

A slice of central Asia in the middle of Berlin.

This futuristic German spa allows visitors to float in a pool of salt water while zoning out to underwater techno.

A bit of retro transportation flair preserved in the world's largest department store.

The original toys that inspired the beloved children's stories are on display at the New York Public Library.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

A miniature rainforest is growing inside of a Midtown Manhattan office building.

Elevated freight railway turned wildly successful urban park.

This beautiful building in the heart of Manhattan's Financial District was empty for decades.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

This Communist-era residential block is one of the longest residential building in Europe.

Modern art commemorates one of the first military actions of World War II.

This antique thermometer honors the creator of the first universal temperature scale.

These rare statues are one of the few remaining material witnesses to Old Prussian culture.

A mysterious emblem tucked in an small alleyway is actually the coat of arms of a heroic medieval family.

Memorial to the lost dead of Gdansk, whose resting places were destroyed during World War II.

The site of the first battle of World War II.

A sweet museum focused on beets.