Cold War Sites

General Information

  Created 26-02-2002   Last update 04-04-2014

Portsmouth & the Cold War

The Portsmouth area presented a number of top priority targets during the Cold War era:

  • Fort Southwick - Commander in Chief Naval Home Command. This was a 'Category A' target and would have attracted 2 nuclear weapons alone - one primary and one back-up

  • Gosport Naval victualling, oiling and munitions depots 
  • HM Naval Base Portsmouth
The nearest United States base (US Army Marine Fleet HQ) was at Hythe near Southampton. As far as can be made out the former Soviet Union had 4 one megaton thermonuclear weapons aimed at the general area of Portsmouth, and a casualty rate of 95% was predicted; the highest in the UK.

Below is an edited list of targets in the Portsmouth area taken from a document dated 1967. 

Atomic weapon target list
 Crown Copyright


Below is an account supplied by Peter Cobb regarding the Cold War re-use of WWII shelters. The two deep tunnel shelters in Portsdown were evaluated for this purpose.

Notice to Readers. These extracts are culled from original documents which are Crown Copyright, held in the National Archives, PRO KEW, London and are reproduced by courtesy of the National Archives. (C). The Original references numbers are HO205/270 & HO205/271 respectively. 

After US, British, Swiss and Canadian Scientific Missions had gone to Hiroshima and Nagasaki, Japan 1945 and '46, and then as a result of experiments carried first ~Shoeburyness, Essex and latterly Orfordness, Suffolk, 1947-56 new policies were drawn up by HM Governments. In 1948 an "Interdepartmental Conference" was called for and met in the temporary Offices of the Home Office at 10 Old Bailey on Wednesday l9 May starting at l500hours. At this Conference were Civil Servants from the Home Office, Ministry of Defence, Ministry of Transport, Ministry of Fuel and Power, Ministry of Supply, Ministry of Works and from the Ministry of Health. An advisor from the Royal Geological Society also attended. One result of that Conference was a Home Office sponsored survey of all known existing shelters remaining from the 1939-45 war (Item 370) and in addition, any other underground structures, be they Caves, Caverns, Tunnels or Mines that could be used in the event of any future (from that date 1948/9) conflict that were within a "reasonable distance of an Urban Area". 

Peter Cobb November 2003



NEW 04-04-2014


I came across your site while looking for info on a Civil Defence underground room that I visited once or twice when I joined the Civil Defence in the early 1960s. It was located in the coal-yard(?) on the left of the bridge at Havant as you look toward Rowland's Castle.

There was a map up on the wall showing concentric rings around Ground Zero, with estimations of how many survivors there might be in each ring after a nuclear bomb of a certain size was dropped, and details on communication and aid in the event of such a happening. All old hat now I suppose, but even then I wondered how any plan to help would work in the closest zones given the amount of radiation projected: no phone lines working, no roads etc. We were issued with personal dosimeter sticks – it all seemed quite exciting in a distant sort of way.

The area is now a car-park and shopping area, and whenever we go there I wonder what became of the ‘secret room’ and if it might still be there.

Pat Weedon - April 2014