A collection of artifacts from Maryland's maritime past.

This Upper East Side apartment co-op was designed as a tuberculosis sanitarium.

This futuristic airport terminal was abandoned for decades before reopening as a hotel—with a vintage plane of its own parked out back.

The ballpark in "Pigtown" where the Brooklyn Dodgers made their name was replaced with a huge apartment complex.

This wall on a street corner in Lower Manhattan has been a blank canvas for a rotation of renowned artists since the 1980s.

A derelict bit of transportation infrastructure hidden in the woods.

Baltimore's classic clock tower was once topped by a rotating, 20-ton medicine bottle.

A swimming hole in the historic industrial quarry that supplied the marble for the Baltimore Washington Monument.

A tour de force of a fountain, memorializing a man who loved fountains more than anything else.

A daily replay of the experiment that proved the rotation of the Earth.

Built by the patriotic residents of Boonsboro in a single day.

A reminder to choose water over wine since 1888.

The grand, column-fronted, sculpture-adorned home of the ambitious digital library.

Before Nixon, "watergate" meant canals.

Fittingly, America's museum of architecture is itself a magnificently designed old building.

This bug-eyed water wheel uses the power of the Sun to clean up Baltimore Harbor.

In an odd geographic anomaly this city borders two different states on opposite sides of town.

Look closely and you’ll notice that the color changes a third of the way up the tower.

Once a black market electronics marketplace, now an otaku shopper's paradise.

The oldest Dutch colonial stone house in New York City is a hidden gem on the border of Brooklyn and Queens.

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

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

Iceland's largest geothermal mud pool is a little bit haunted and a little bit dangerous.

The "Seinfeld" diner.