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

A clock set into the concrete outside a Manhattan jeweler has been telling time underfoot for over a century.

Unrepaired walls from a 1920 anarchist bomb attack.

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

Amid the bustle and noise of the Financial District hides a secluded garden oasis above the city streets.

Avoid gangster interaction while window-shopping.

An odd, ancient window that may have once been part of a brutal prison is embedded in the side of New York's Police Plaza.

Elevated freight railway turned wildly successful urban park.

A collection of items from a way of life that no longer exists.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

Several plaster noses are hidden in plain sight around London's Soho neighborhood.

The signs of a long buried road can still be found hidden beneath a London sewer grate.

This churchyard arbor is surrounded by hundreds of gravestones placed there by author Thomas Hardy.

An unusual round church in London with a Templar past.

A 300-year-old tea shop that brought tea to the English people, not to mention the Queen herself.

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

Possibly the world's largest hourglass only needs to be reset every New Year's Eve.

This statue of a falling man commemorates a teenage martyr of the Hungarian Revolution.

The romantic garden was the epicenter of the Hungarian art scene in the 1880s.

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

A floundering Polish shipyard was once the soul of the Solidarity movement that capsized communism.

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

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

The site of the first battle of World War II.