This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.

America's greatest forgotten garden and the former stomping grounds of Son of Sam.

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

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

A beautiful multicolored mound formed by the mineral deposits of the Orenda Spring.

Once a sewer culvert, this road tunnel now offers cyclists and pedestrians a subterranean stroll under the C&O Canal.

Now abandoned, the first public health hospital in the U.S. saw more than one million immigrants from around the world.

The world's largest public collection of PEZ memorabilia.

Ruins of a historic medical facility sits eerily by the water.

This water tower commemorates the invention of the transistor on this site in 1947.

An allegedly cursed tree represents a town's reckoning with a racist past.

American involvement in World War I officially ended in 1921 in New Jersey, three years late and thousands of miles from the battlefield.

Historic town settled in the 19th century because of its convenient location along a popular coal transport route.

A giant light 13 feet high shines near Thomas Edison's old Menlo Park lab.

Several times a year, during low tide, two pairs of historic train tracks are revealed on this New Jersey beach.

Destructive children, start your engines.

A bronze monument to the infamous radio broadcast in the real New Jersey town where the fictional Martians crash-landed.

This private island is still in the family after a 400-year history including a witch hunt and a pirate.

A tiny islet just off Long Island offers a wealth of infectious curiosities.

Want to build a wind turbine? Secede from the nation.

An abandoned Gold Coast-era mansion once intended for the exiled ruler of Albania, who never arrived.

The abandoned grounds and derelict greenhouses of this once-magnificent Edwardian estate are now a nature preserve open for exploration.

This abandoned artificial island off the coast of New York City is now home to dozens of harbor seals.