Two thousand artifacts from around the world collected by one woman who loved to travel.

This upscale streetwear store is hidden behind a fake Snapple machine in the back of a deli.

An enormous, inside-out glass globe built in 1935.

A morbid secret lies hidden within the beautiful walls of the Boston Athenaeum.

An annual extravaganza of Broadway theater memorabilia.

The 28-foot granite map plots the locations of 40 theaters in New York City.

One of the few remaining American elm trees in New York’s Tompkins Square Park was the birthplace of a new religion.

A notorious punk house turned co-op.

A hands-on traveling collection of the innovative devices of yesteryear.

Lie in a hammock where George Washington stood.

The name of this famed hospital was once a byword for the horrors of medical and psychiatric care.

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

A semi-scholarly approach to sex.

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

This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

Order scoops of pandan, lychee, and black sesame at this family-run institution.

A terrific purveyor of natural history objects and curios.

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

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

A historic neighborhood church is reborn as a psychedelic arts collective.

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

A Spiritualist house of worship where believers communicate with the dead in the spirit world.

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.

A monument in Washington D.C. marks the spot from which all other roads were supposed to stem.