A beautifully rebuilt windmill from the 17th century, situated along the Amstel River.

This mysterious pyramid is said to be part of a complex web of occult and Freemason symbols.

This educational institution and reference library specialize in the psychic arts and mediumship.

Historic cuisine meets fine dining in a hotel-restaurant overlooking Hyde Park.

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

A small hippo-shaped fountain in Berlin, Germany.

Largely overlooked, this little fountain on Museum Island is a whimsical tribute to a Prussian king nicknamed the “Fatty Flounder.”

Order bagels and lox from an iconic Jewish delicatessen with nearly a century of history behind it.

Designed by the architect who also had a hand in crafting the Westminster Abbey and Bristol Cathedral.

Art Deco and “Wrenaissance” mash-up, this recently restored royal residence has been home to kings and comes with secret monkey passages included.

This toxic spoil heap found a second life as a ski slope, popular film location, and wildlife haven.

3,000 family pets and military animals are buried in this London graveyard.

One of London’s rare Tudor-era buildings is a fate-defying gatehouse for a church.

The palace window through which Protestant nobles flung two Catholic regents, thus sparking the Thirty Years' War.

A mysterious suspended hand greets unsuspecting visitors at the Tower of London.

A jumble of concrete on the corner of one of London’s terraced buildings is actually a work of art.

Visit the grave of a famous feminist author and the mother of Mary Shelley.

These stained-glass windows are all that remains of a building that was the target of one of the biggest explosions in London after World War II.

Several colorful mosaic panels depict the life and creative genius of the Master of Suspense.

A rare tour of an aristocrat's private home reveals valuable 17th-century paintings from artists like Rembrandt.

Dine at a legendary after-hours joint frequented by David Bowie and Iggy Pop.

A statue of an astronomer gazes at the sky as a tribute to Caroline Herschel.

The best bagels in Berlin are tucked away in an independent bookstore.

A helicopter memorial commemorating what was once the only way to access this West Berlin exclave.