A former zoo turned public park, where visitors can hang out in the old animal cages.

This mysterious artificial cave has long puzzled New Englanders.

Utopia and nostalgia mingle at the site of Bronson Alcott's ill-fated agrarian commune.

A short walk through the woods will take you to an unusual flat hill top, used by the Shakers for outdoor worship.

This Gothic castle was inspired by Erik the Red's Viking residence at Brattahlid in Greenland.

The oldest living cultivated fruit tree in North America.

In the middle of a New England forest sit the crumbling ruins of World War II-era ammunition storage bunkers.

The sprawling, eccentric estate of Ames and Ames, a brilliant botanist, and a genius inventor and artist.

Plans for this peninsula included houses, the United Nations Headquarters, and a nuclear power plant. When none of them worked out, it became an expansive park.

This memorial garden is the final resting place of many beloved pets including that of a famous explorer.

A historic bridge with a lovely acoustic anomaly.

Once the largest public hospital for the mentally ill was also surrounded by controversy.

This headstone-like marker inscribed with three words has been an utter mystery for over a century.

Solar powered Spectacle Island features all-green facilities.

Run by a eugenics advocate, this aging institution conducted secret radiation experiments sponsored by Quaker Oats.

The history of the tea trade is told in bas-relief on this historic pair of Boston doors.

An easy-to-miss garden in Boston's North End honors the mother of JFK and others who lost children in WWII.

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

One of the last remaining World War II Victory Gardens in the U.S. is quietly growing across from Fenway Park.

A tiny monument to the classic American candy.

The strikingly modern structure stands out among the brick buildings speckling the Harvard Business School's campus.

Impossibly life-like natural history models created out of glass by a father and son.

Three prestigious academic collections come together to create a world-class natural history museum.

This hidden labyrinth offers walkers some brief peace of mind.