Painstakingly built dioramas sit unnoticed in a Boston office building.

From bench to vandalism to art, this silly prank seat was funny enough to become permanent.

Mrs. Mallard and her brood are a beloved fixture in Boston Public Garden.

The massive machine creates cracking displays of indoor lightning.

Narrowest house in Boston.

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

The site of one of the strangest disasters in history—a wave of deadly molasses traveling at 35 mph.

Radical Bookstore and Community Space.

19th-century operating theatre in which the use of ether was first demonstrated - plus, a skeleton and a mummy!

One of the now-less-hidden floral gems of the "Emerald Necklace."

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

The Boston square dedicated to the dark poet who was born nearby.

This upscale streetwear store is hidden behind a fake Snapple machine in the back of a deli.

A morbid secret lies hidden within the beautiful walls of the Boston Athenaeum.

One of the oldest used bookstores in the U.S. has been selling antiquarian treasures since 1825.

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

A beautiful Victorian-era cemetery, complete with a miniature village.

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

One man's hand-sculpted collection of colorful masks representing a host of gruesome spirits.

This private museum is packed with 20th-century traffic and technology artifacts.

This botanical garden boasts sculptures, industrial ruins, and an endorsement from the Dalai Lama.

A trail of "Game of Thrones"-themed doors carved from fallen trees from the iconic Dark Hedges.

This towering church is home to a world-famous organ and a treasure trove of medieval art.

An abandoned 1930s gas station turned bustling neighborhood park.