Once the tallest building in the world and the site of "the highest dinner ever held in New York" this building now holds the most expensive penthouse in the city.

A three-story copper skybridge connects two Manhattan buildings with Art Deco luxury.

Mysterious 500-year-old tapestries depict a unicorn hunt.

A historic 1890s architectural masterpiece with an iconic clock tower that, once open to the public, now faces an uncertain future.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

A crumbling hospital from the 1850s on Roosevelt Island.

This beautiful building in the heart of Manhattan's Financial District was empty for decades.

A terrific purveyor of natural history objects and curios.

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

A pedestrian island in the middle of world-famous Times Square emits a strange (and purposeful) humming noise.

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