| South Boston Naval Annex | |
|---|---|
| South Boston, Massachusetts | |
 The Annex, circa 1958. In this image, South is on top. | |
| Type | Shipyard annex |
| Site information | |
| Controlled by | United States Navy |
| Site history | |
| Built | 1920 |
| In use | 1920–1974 |
The South Boston Naval Annex was a 167-acre (68 ha) United States Navy shipyard annex located in South Boston. It was the annex of the Boston Navy Yard, and was operational from the 1920 to 1974, when it was closed along with the main shipyard. The annex is also home to Dry Dock Number 3, one of the largest dry docks on the East Coast. Most of the former annex site was listed on the National Register of Historic Places in 2022.[1]