This tiny, painted door at the base of a tree stump has been a fixture of the Harvard University campus for decades.

Two thousand artifacts from around the world collected by one woman who loved to travel.

This bridge was the birthplace of a unit of measurement based on a fraternity joke.

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

Berthed at the Charlestown Navy Yard in Boston, "Old Ironsides" is the oldest commissioned warship still afloat.

This landmark cemetery in Boston was created more than 300 years ago.

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

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

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

The legendary building that needed ghostly approval before being built.

This iconic L.A. bookshop is housed in an abandoned bank—both symbolic and chic.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

The Cambridge pub where Francis Crick announced that he and James Watson had discovered the DNA double-helix.

This serene oasis in an affluent Los Angeles neighborhood holds some of Gandhi's ashes and got Elvis into Eastern Philosophy.