One of the Northern Territory's most important heritage sites, Fannie Bay Gaol operated as a Gaol and Labour Prison in Darwin from September 1883 until 1979. The complex was extensively damaged by Cyclone Tracy in 1974, and was repaired and re-opened after the cyclone. Its long-term viability had come to an end, however, and it was closed 4 years after re-opening. Fannie Bay Gaol Museum, a regional history museum, is located in a heritage listed gaol complex.

Fannie Bay Gaol Museum still houses the old gallows used for the last execution in the Northern Territory in 1952. The museum has a variety of interesting displays including the mess area, the women's section of the gaol, and a Cyclone Tracy display with outstanding photographic reference & video footage of the disaster.

The original building comprises Blocks A and B containing six cells, and a kitchen and a wash house. The Infirmary was added in 1887 and contains the gallows installed for the last executions held in the Territory in 1952.