Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

An small and easily overlooked archaeology museum chock full of Egyptian artifacts.

Repository for more than 22 million pickled specimens.

Eighty million natural history specimens call this gargantuan museum home.

Some 80,000 Delft Blue tiles line the inside of this Amsterdam walkway.

In the days before house numbers, these colorful signs held clues about various buildings' purposes.

Europe's official "zero-level," the equator of elevation.

Amsterdam's former hotspot for public executions and dissections.

A unique collection of gilded age mechanical pianos.

Famed for its pie, this eatery has a hidden tunnel that allowed Catholics to secretly walk to church during the Reformation.

A Dutch passageway's artistic, aquatic-themed makeover pays tribute to the capital city's famed waterways.

Seven mini rowhouses fill the gap between 54 and 70 Westerstraat.

Tucked in the back of a flower shop, its collection details the fascinating history of the Netherlands's iconic symbol.

A hidden church in a hidden courtyard tells the story of the Miracle of Amsterdam.

A floating cat sanctuary on an Amsterdam canal.

Amsterdam's narrowest house facade is a monument to 17th-century tax evasion.

Europe's first floating restaurant is home to a hilarious legend.

This 22-floor tower's Skydeck offers panoramic views of Amsterdam.

This historic Amsterdam bar used to accept sailor's monkeys as payment.

The tallest church in Mechelen might have been the tallest in the world if not for a lack of funds.

A Dutch clog company in the town of Zaandam loves the wooden shoes so much it made a museum for them.

The place where Czar Peter I of Russia resided in 1697 during his Grand Embassy.

The final home of the legendary Danish sailor said to have lived to be 146 years old.

A symbol for the opposition to nuclear power around the world.