The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.

This rugged area of red rocks and arches is often considered one of the most beautiful places on Earth.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

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

The 340-year-old house that inspired the classic Nathaniel Hawthorne novel.

The only structure left with direct ties to the Salem witchcraft trials of 1692.

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

A Natural History and Science Emporium.

This sculptural piece by the artist Tom Otterness doubles as a jungle gym.

This pole near the infield rail at Belmont Park marks the jaw-dropping margin of Secretariat’s 1973 Belmont Stakes victory.

A unique work of art that was created without permission.

Home to the abandoned Tioronda Hat Works Factory, this park is a combination of woodlands and marshlands.

Here be dragons.

A living antique aviation museum in the historic town of Red Hook, New York.

Reforestation in action is the main attraction in this abandoned quarry.

An unassuming island in the middle of the Hudson that hosts campers, including Aleister Crowley.

A reminder to choose water over wine since 1888.

This sprawling woodland estate was the brainchild of iconic American industrial designer Russel Wright.

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

The Hudson River School comes alive at this palatial estate.

The dairy farm in upstate New York where nearly half a million people gathered for three days of peace and music in 1969.

The life of one of FDR's possible mistresses is preserved in her palatial Hudson Valley mansion.

The remains of what was once the world's steepest passenger funicular.

A self-made museum in Queens, New York continues to display the work of a sculptor known for paving his own way.