South Street Cemetery is located on South Street and Sagamore Avenue (NH-1A) at the mouth of the Piscataqua River.

South Street Cemetery is a large complex of five cemeteries that date back to the colonial era. The cemeteries are Cotton, Elmwood, Harmony Grove, Proprietors, and Sagamore. They contain over 3,000 graves of prominent and ordinary citizens of Portsmouth, some with elaborate and historic headstones. The cemetery is maintained by the Griffin family and the City of Portsmouth, and it features a pond in the center.