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

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

The first neighborhood to implement the Garden City model in its suburban planning.

An isolated beacon with a history of grisly murder and a view of some of literature's greatest inspirations.

The first dish to bounce radio signals off the Moon, it was the forerunner to the U.S. Space Program.

Believe It or Not, Ripley once called this chiseled mountainside “New York’s Mount Rushmore”.

A quaint museum nestled in a former hub of Irish moss harvesting.

Built to bless whalers before their voyages, this Massachusetts church now features a ship-shaped pulpit.

Plymouth's huge yet little-known memorial to the Pilgrims.

A famous songsmith's custom piano, dubbed "High Society," is hidden just out of sight in one of New York's finest hotels.

A historic custom house with ties to George Washington is now a shrine to local nautical history.

The first bell ever cast in Boston was cast by Paul Revere...and sounded terrible.

This massive tea kettle was once a promotional stunt for the Oriental Teashop.

Beautiful steampunk ghosts of early Massachusetts.

The oldest Italian café in Boston, this spot also serves as a veritable museum of vintage coffee ephemera.

An eccentric inventor's castle home with its own indoor weather system.

These "mermaids" that surround a plaza in Segovia are rather sphinx-like.

World War II-era bunkers are hidden under the beaches of this picturesque park, which is still scattered with wartime watchtowers.

The historic home still shows the scars from a little run-in with the British in 1813.

The famous author's cottage hideaway.

Centuries of crashing waves carved out this small hole in the rock, which lights up at certain parts of the year.

The real-life site of Ichabod Crane's infamous gourd attack.

This magnificent castle grew from a small Moorish fortress, and reportedly inspired two iconic Disney castles.

This nearly 200-year-old restaurant's history includes an exiled French prince, JFK, and a very hungry Daniel Webster.