It encompasses an industrial factory complex, most of which was historically associated with the Walter Baker & Company, the first major maker of chocolate products in the United States.
The district is bounded on the south by the MBTA rail right-of-way in Milton and River, Washington, and Adams Streets in Dorchester.
They are stylistically diverse, having been built between 1868 and 1947, reflecting styles from the Second Empire to the Queen Anne, Romanesque Revival, and utilitarian modern.
They had occupied parcels of land near what is today the Ventura Street Playground in the Neponset River Reservation and Dorchester Park.
Additional expansion took place in the late 19th century, when a major portion of the present complex was built beginning in 1868 under the leadership of Henry Pierce; it continued under his successor, H. Clifford Gallagher.