This platform is now a memorial dedicated to those who were deported during the Holocaust.

The only subway station in the city that still makes use of gap fillers.

An abstract and eyecatching clock/fountain is the centerpiece of this little-known German city.

This unique medieval artwork featuring the story of the Antichrist remained lost for decades.

The oldest continuously-operated inn in the United States, once owned by Henry Ford.

This conical hill was built as a testing ground for an engineer known as the Glider King.

Standing atop 2nd-century Roman ruins, this church is one of the oldest and most iconic in Old Cairo.

A memorial in the Tiergarten is a reminder of the suffering inflicted on homosexuals by the Nazi regime.

Tourists often confuse this beautifully ornate former cigarette factory for a mosque.

A cruise terminal that changes the atmosphere of Red Hook's industrial waterfront.

This beautiful Brooklyn monument over a crypt memorializes a grim and largely unknown story from the American Revolution.

Retribution for death of infamous mob boss Franie Yale was a case of mistaken identity.

This former crime corner has been turned into an eclectic community center.

This exemplar of modernist architecture is meant to captivate and inspire students of the Cooper Union.

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

During the holidays, a vintage subway train whisks New Yorkers back in time.

A masterpiece of LGBT art has been restored in what may now be the most valuable restroom in America.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

New York City's smallest piece of private property.

One of only two commuter aerial tramways in the United States.

A crumbling hospital from the 1850s on Roosevelt Island.

A terrific purveyor of natural history objects and curios.

No one really knows how these old hobby horses got here, but the herd keeps growing.

Solar observatory doubles as a daring display of Expressionist architecture, much to Einstein's chagrin.