Fort Southwick

Fort Southwick
Aerial view of the fort
Fort Southwick
Coordinates	50°51′32″N 1°06′31″W / 50.858777°N 1.108506°W / 50.858777; -1.108506
Site information
Open to the public	No
Condition	Complete
Site history
Built	1861-1870
Materials	Earth Brick

Fort Southwick is one of the forts found on Portsdown Hill, which overlooks the naval base of Portsmouth in the county of Hampshire, England.

Fort Southwick was built to defend the landward approaches to the naval base on the recommendation of the Royal Commission on the Defence of the United Kingdom which reported in 1860.

It is the highest fort on the hill, and holds the water storage tanks for the other forts, supplying them via a brick lined aqueduct. Construction was started in 1861 and completed by 1870. It was designed to house a large complement of men (about 220) in a crescent-shaped barrack block. Its north projection has one full caponier to defend the dry ditch, and has two smaller demi-caponiers at the corners. A small musketry gallery crosses the ditch at the south-west angle to cover a minor branch of the ditch. Mortar batteries of five mortars each can be found set into the rampart behind the demi-caponiers.

In 1893 the fort was armed with a total of 23 guns:

• Nine 64 pounder rifled muzzle-loading guns
• Eight 7-inch rifled breech-loading (RBL) guns
• Six 8 in (20.3 cm) rifled muzzle loaded howitzers (three were on ground platforms; the other three on travelling carriages)

A central spiral staircase from the surface gives access to four main tunnels running radially outward from it at uneven angles. These tunnels lead to the barrack block and caponiers, and past the magazine.

During the Second World War, Underground Headquarters of UGHQ, the communications "nerve centre" for Operation Overlord, was in a secret network of tunnels excavated between February and December 1942 by 172 Tunnelling Company of the Royal Engineers 100 ft (30 m) underneath Fort Southwick, well out of reach of any bombs of the era. The call sign of this base was 'MIN'.

Although disarmed in 1906, the fort was retained by the military as a barracks, and also used to train soldiers how to capture and hold a fort. It became a demobilisation centre for three years after the First World War. The fort was part of the Admiralty Research Establishment until 2002, when all operational use of the fort ceased. It was sold by the Ministry of Defence in July 2003 to the "Fort Southwick Company Limited", who intend to convert the barrack block into luxury apartments.^[1] The site is currently occupied by the NHS and includes a staff park and ride service to Queen Alexandra Hospital.^[2]

It has been a Grade I Listed Building since 1987.^[3][4]

• Hogg, Ian V (1974). Coast Defences of England and Wales 1856-1956. David & Charles. ISBN 0-7153 6353-0.

Wikimedia Commons has media related to Fort Southwick.

• Palmerston Fort Society
• Victorian Forts data sheet
• Fort Southwick
• Fort Southwick UGHQ
• Walk the Story > Fort Southwick
• Fort Southwick NATO Communications Centre
• UCAP Airsoft Site and tours of the Southwick UGHQ
• Fort Southwick on mb21 Archived 28 July 2010 at the Wayback Machine