If it hadn't been caught in time, a flaw in the design of this Manhattan skyscraper could have led to its collapse.

Once a flowing stream and where the USS Monitor, the world's first ironclad, was built and launched.

The childhood home of one of America's greatest unsung troubadours still stands in a much changed Brooklyn neighborhood.

A group dedicated to promoting boating, kayaking and environmental education programs.

Fabrication workshop where the encasement for One World Trade Center's beacon was constructed.

The rare American Civil War-era weapon was never fired in anger.

After surviving abandonment, this powerful Latin American mural is alive again.

Creating this diorama spurred naturalist Carl Akeley to begin advocating to protect the apes.

Staten Island's original central park is the former home of the city water supply as well as thousands of immigrant graves.

Compensation for the destruction of a historic shipyard.

The most radioactive spot in New York City can also fix your muffler.

Headquarters of the world's fourth largest Hasidic sect and the first of many "770s" around the world.

A remnant of the original World Trade Center complex continues to serve as a commuter gateway.

This unusual apartment building may be Brooklyn's own version of the Leaning Tower of Pisa.

Once called Winthrop Park in 1889, home to a decidedly sexy tribute to the Monitor vs. Merrimac battle.

Storage warehouse of the rich and famous.

This recently uncovered ad for Lindsay's run at Mayor in 1965 had been hiding for decades underneath a billboard.

The highest rapid transit station in the world.

This unique house, the only one of its kind in Brooklyn, was built as part of a real estate developer's showcase.

An activist who committed her life to peace and women's suffrage.

A playground the size of a city block is a modernist monument to civic values and public housing.

Enormous one time fiber mill now houses local artists and small businesses.

A drawbridge named for a potentially intersex Polish national who fought alongside George Washington during the American Revolution, and an example of "Pulaski Red".

If you were standing here on October 5th, 1950, you'd be dead.