This relic of 19th-century infrastructure is one of the few remaining coal gas storage tanks in the U.S.

The original toys that inspired the beloved children's stories are on display at the New York Public Library.

This hidden oasis features a stunning view of the Hudson River and the Palisades from a castle-like museum.

The former estate of the Guggenheims, part of the opulent Gold Coast that inspired the Great Gatsby.

Seven people are buried in the middle of what's now a movie theater parking lot.

A 13,000-year-old mastodon skeleton was found during the construction of a 19th-century New York mill.

A CT scan revealed the identity of this 3,000-year-old mummy that everyone erroneously thought was female.

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

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

Was there a small "backpack nuke" hidden in the attic? JFK apparently thought so.

A crumbling hospital from the 1850s on Roosevelt Island.

One of only two commuter aerial tramways in the United States.

The massive machine creates cracking displays of indoor lightning.

One of the most scenic falls in Massachusetts has a history of death and grim legend.

An uber-secure, windowless tower of doom in the center of Manhattan is an NSA spyscraper.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

Blighted Irish field and the ruins of a 19th-century cottage on the edge of urban Manhattan.

Currently housing a corporate bank branch this building at the southern tip of Manhattan was once the gateway to luxury vacationing.

Built hundreds of years ago this downtown iron barrier once protected a much despised king.

Twice a day one of these tragic bronze mariners drowns with the tide to remember all those the sea has taken.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

Amid the bustle and noise of the Financial District hides a secluded garden oasis above the city streets.

The most confusing clock in New York.

Set sail on a small scale.