Statue commemorating the use of ether in anesthesia.

American revolutionaries and British soldiers alike are buried here in the fourth-ever cemetery in Boston.

No one messes with the Massachusetts sacred cod, not this time...

An easy-to-miss garden in Boston's North End honors the mother of JFK and others who lost children in WWII.

A plaque memorializes the Boston location of one of the largest nightclub fires in history.

This monument on Breed's Hill proves that one of the most famous battles of the Revolutionary War is misnamed.

The first bell ever cast in Boston was cast by Paul Revere...and sounded terrible.

A grand New York post office that is home to mailman Santas, scraps of postal history, and a pneumatic mail system.

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

A touching tribute to the "Queen of Soul."

Fake subway tiles were installed to cover a design that resembled the Confederate flag—it's unclear if the resemblance was intentional.

Two large-scale sculptures of Adam and Eve greet visitors in the nude at the Time Warner Center in NYC.

Stunningly detailed mosaics in a New York subway station bring life to the Weimaraners of artist William Wegman's work—and to thousands of commutes.

This curved Manhattan building was built to house the opulence of John D. Rockefeller's oil empire.

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

This Dutch Colonial home is the oldest remaining farmhouse in Manhattan.

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.

The fanciest public restroom in New York City boasts fresh flowers, art, and a classical music soundtrack.

The oldest surviving bridge in New York City, which reopened to pedestrians in 2015.

The oldest operating apothecary in the US has treated everyone from Thomas Edison to Mark Twain.

Try not to get slimed in Tribeca.

Famously misunderstood wonder of the ancient world

The picturesque birthplace of Icelandic democracy is drenched in the blood of its brutal past.

This stunning concert hall has become a symbol of Iceland's national recovery.