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

Marvel at this turn-of-the-century masterpiece that has been turned into a rather stately supermarket.

Lie in a hammock where George Washington stood.

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

Ride the subways of yesteryear.

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

Elevated freight railway turned wildly successful urban park.

Try not to get slimed in Tribeca.

On the Hudson resides one of the largest clocks in the world.

Stolen goods adorn the organ at Old North Church.

Statue in Salem of the woman who starred as the witch Samantha in the sitcom "Bewitched."

Equal parts record-breaking temple to consumerism and bizarre fun park, it's more than you think it is...

A downtown park built on top of unclaimed graves.

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

A former waterfront market is now in the center of town due to some interesting Boston engineering.

This monument on Breed's Hill proves that one of the most famous battles of the Revolutionary War is misnamed.

The site of Paul Revere's historic two lantern warning.

The American Revolution was galvanized into serious action due to the tragic clash with British soldiers that occurred at this location.

Narrowest house in Boston.

Macabre headstones carved with winged skulls, dancing skeletons, and pithy reminders of impending death.

Deep scars on the earth left by the Ice Age.

The world's largest rotating world.

Cleveland's giant "free" stamp is a nod to the Civil War, but was misinterpreted for years.

Funded by John D. Rockefeller, this is one of the earliest, and most beautiful, shopping arcades in America.