World's first "penitentiary," meant to be humane, drove men insane.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

New York City's smallest piece of private property.

The most confusing clock in New York.

A terrific purveyor of natural history objects and curios.

Panoramic views of the city of New Haven and the Long Island Sound, with a side of history.

With some 500,000 books across five buildings, this bookstore is a reader's paradise.

A graceful natural rock formation stands astride the point where the Gulf of California meets the Pacific Ocean.

This city square is home to Amsterdam's oldest church and a statue honoring Dutch sex workers.

A beer pipeline runs beneath Bruges.

A stone slab in Madrid marks the point from which the distances of Spain's national roads are measured.

An ancient Egyptian temple in the middle of Madrid, Spain.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

The mummified right fist of a 1,000-year-old saint-king sits inside an ornate golden reliquary.

Uh, pardon me, ma'am, but I couldn't help noticing that there's a Columbo statue in the middle of Budapest.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

The statue of John Harvard isn't actually John Harvard—or even, technically, the founder of the school.

This nearly endless university hallway is home to a unique sunset known as "MIThenge."

An artist's cute bronze subway sculptures belie his violent artistic past.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

Beautiful mosaics cover the first stations opened on New York City's newest subway line.

Commemorating the spot where the famous scientist fed his pigeons.