Established by the National Park Service in 1996,[1] the district is situated between downtown Lynn and the Atlantic Ocean—bounded roughly by Broad and Lewis Streets to the north, Lynn Shore Drive to the southeast, Nahant Street to the west, and Eastern Avenue to the east.

Most of the District's earliest surviving houses are conservative, 2.5-story, center-chimney Federal buildings, but several Greek Revival structures also are extant.

[2] The Diamond District was substantially developed after 1840, when the area became a fashionable coastal summer resort.

The style best represented is Colonial Revival, with numerous exemplars built between 1890 and 1940—notably the Charles Lovejoy House, which was added to the National Register in 1978.

Although predominantly residential, the Diamond District includes a handful of commercial buildings, which are located on Broad and Lewis Streets.