Beneath Denmark's Højbro bridge, a bronze merman and his seven sons forever mourn for the mother and wife who left them for land.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

Hotel designed by indie graphics artists.

Copenhagen's celebrated theme park and gardens.

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

Michael Jackson got Bad and Crocodile Dundee walked on heads in this iconic Brooklyn subway station.

A legendary speakeasy bookstore returns from the brink.

Try not to get slimed in Tribeca.

This London pub hides a peculiar secret: a recreation of the rooms shared at 221b Baker Street by Sherlock Holmes and Dr. Watson.

What happens here stays here – unless it affects the whole world.

The oldest living tree in Manhattan comes shrouded in sinister legend.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

A Manhattan courthouse hides a small but scathing memorial to Holocaust injustice.

An uber-secure, windowless tower of doom in the center of Manhattan is an NSA spyscraper.

A grand New York post office that is home to mailman Santas, scraps of postal history, and a pneumatic mail system.

There must be a pun in this haystack somewhere...

Red frames showcase remnants of one of New York's original subway stations.

A drawbridge named for a potentially intersex Polish national who fought alongside George Washington during the American Revolution, and an example of "Pulaski Red".

Salute the leader of the proletariat.

In its day this historic fort held 100 cannons pointed in almost every direction to protect New York.

The notorious headquarters of a corrupt political machine.

The most confusing clock in New York.

A very classy 1920s-era bar right in Grand Central Station.