Former home of an abolitionist couple who escaped slavery and established the most active Underground Railroad stop in Boston.

The Boston home of a conductor on the Underground Railroad.

This faux Greek Revival mansion is a clever optical illusion tucked into a Beacon Hill alley.

A plaque marking the famous abolitionist's birthplace often overlooked by visitors to the nearby Charles Sumner House.

Historic home of a Black veteran of the American Revolution and one of the earliest civil rights activists in the United States.

In the 19th century, this was the center of Boston's Black community.

A stone marker commemorating the first time sound was transmitted over wires.

A tiny plaque marks the location of the water source that facilitated the birth of modern-day Boston.

A centuries-old church stands as a testament to Boston's "father of architecture."

Tragedy on Little Brewster Island memorialized.

Historic Hull Street was actually the first street with a proper name in the Boston area.

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

"Mock all and sundry things, but leave the saints alone."

A mysterious stone embedded at the base of a historic Boston building.

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

This plaque is dedicated to a historic hotel’s Canine Ambassador and the subject of two children’s books.

A beacon atop a downtown building provides Bostonians with weather forecasts and baseball news.

This historic sculpture from the 16th century is even older than the city of Boston.

A pair of antique trolleys are on display at one of the oldest subway stations in the United States.

This bronze sculpture was inspired by a photograph of Martin Luther King Jr. and his wife embracing after he won the Nobel Peace Prize.

This mosaic commemorates the oldest subway tunnel and station in the United States.

The colonial home of Paul Revere during the American Revolution.

What was once a true peninsula has now been filled in, causing the water to recede and leaving many streetside "waterfronts" and landlocked "islands."

This steep slide at a kids’ playground went viral after an police officer tumbled down it.