It was a former ‘stone frigate’ - a nickname for a land-based naval establishment - and was the home of the Royal Navy’s Maritime Warfare School during the Second World War.
The school was originally based in Portsmouth Dockyard and took its name from the ship used as its tender, but was moved inland to Southwick House just outside the city during the war where it remained until it was moved to HMS Collingwood in Fareham in 2004.
The site was given to the Ministry of Defence in 2005 and is now occupied by the Defence School of Policing and Guarding.