The haunting "Hell House Altar" is one of the few remnants of an abandoned college that has been a magnet for local legends.

This old cement mine has been used as everything from a mushroom farm to a recording studio.

The world's only museum devoted to the wonders of fluorescence.

A lovely aquatic park built by a one-armed Civil War veteran who made a fortune from lotuses.

A dilapidated dock tells the story of Titanic's missed arrival.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

The feral felines of Roosevelt Island have a small army of allies and an abandoned hospital all to themselves.

A Pythagorean funhouse that tries, successfully, to prove that math is the coolest thing ever.

The oldest family-run luncheonette in New York, last renovated in 1948, still serves food and drinks the old-fashioned way.

Manhattan’s Battery Park has a whimsical carousel full of spinning, glowing fish.

This abandoned subway station beneath the Waldorf-Astoria hotel is allegedly used to secretly transport presidents.

Dodge prohibitionists and slide through the telephone booth in Crif Dogs.

A crumbling hospital from the 1850s on Roosevelt Island.

A tiny museum housed in a New York freight elevator specializes in the "overlooked, dismissed, or ignored."

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

One of two lighted lanterns hung in the church belfry on the eve of the Revolutionary War to warn that the British were on their way.

"the sweltering inhabitants of Charleston and New Orleans, of Madras and Bombay and Calcutta, drink at my well . . . The pure Walden water is mingled with the sacred water of the Ganges."

This small section of the Sleepy Hollow Cemetery is rotten with famous authors' graves.

A nostalgic bibliographic gem.

This lonely waterfront memorial to the men of the Titanic was erected by the "Women of America."

A derelict bit of transportation infrastructure hidden in the woods.

This grand gothic brewery has been pumping out suds for over a hundred years.

This 12-foot-tall T-rex is the largest K’Nex skeleton sculpture in the world.

148 feet long and in the middle of a verdant forest.