Home » Resources » UXO City Guides » Portsmouth – UXO City Guide

UXO City Guide
Home Office Bombing Statistics for Portsmouth

Record of German Ordnance dropped on the County Borough of Portsmouth

High Explosive Bombs (All types)


Parachute Mines


Oil Bombs


Phosphorus Bombs


Fire Pots


Pilotless Aircraft (V-1)


Long-range Rocket Bombs (V-2)


Weapons Total


Area Acreage


Number of items per 1,000 acres


Why was Portsmouth targeted and bombed in WWII?

Portsmouth has long been a strategically important port, so when war broke out its naval base and dockyards were considered a prime target for the Luftwaffe.

The first bombs fell on the city on 11 July 1940 with the heaviest period of bombing occurring between August 1940 and March 19411. Not only did unrestricted heavy bombing cause severe damage to swathes of the dockyards, but also to the city’s heart and residential suburbs.

HMNB Portsmouth had been supporting the Royal Navy since the Tudor period and the vast site covered approximately 300 acres, with numerous dry docks, tidal berths and basins.

Initially the Luftwaffe heavily targeted HMNB Portsmouth due to its important role in the war effort. Not only significant as a repair and refit facility for naval vessels, it housed destroyer flotillas that would act as the first line of defence against any German invasion following the fall of France in June 1940.

The Royal Naval Armament Depot at Priddy’s Hard in neighbouring Gosport was also targeted due to its large supplies of torpedoes and sea mines. Many of the old Palmerston Forts which had been regarrisoned at the outbreak of war were also targeted – Fort Cumberland for example was hit in August 19402.

Luftwaffe target photography of Portsmouth.

Home Office Bombing Statistics for Portsmouth

Details obtained from the official Home Office bombing statistics, indicates the quantity and type of bombs that fell on the County Borough of Portsmouth during WWII (excluding incendiary bombs).

A total of 1,297 bombs fell on Portsmouth, equating to an average of 140.6 items of ordnance recorded per 1,000 acres.

Major bombing raids on Portsmouth

In total, there were 67 attacks on Portsmouth over the course of four years with three major raids occurring on:

  • 24 August 1940 – 125 casualties.
  • 10 January 1941 – 171 casualties.
  • 27 April 1941 – 102 casualties3.

Portsmouth sustained a high density of bombing, and German air raids on Portsmouth between 1940 and 1944 killed 930 people – while an estimated 1,216 were left hospitalised4. The close proximity of military installations to civilian areas of Portsmouth increased the risk of casualties.

Approximately 10 per cent of the city’s 63,000 homes were destroyed, 6,000 properties received significant bomb damage and an additional 69,000 suffered some form of damage5. The raid of 24 August 1940, where the Luftwaffe dropped 60 high explosive (HE) bombs, led to 117 deaths alone6. The Princes Theatre on Lake Road took a direct hit and was demolished during the raid.

Further destruction was caused by the raid of 10 January 1941. Prior to dropping their HE bombs, German aircraft dropped hundreds of incendiary bombs (IBs), causing widespread fires across the city.

The shopping centres at Kings Road, Palmerston Road, and Commercial Road were all destroyed. Clarence Pier was severely damaged by fire, while the George Hotel in Old Portsmouth was completely lost. Other important structures severely damaged during this raid included part of the Royal Hospital, Connaught Drill Hall, Dockyard School and the Hippodrome7.

April 1941 saw numerous attacks on Portsmouth, the raid of the 27 April had the greatest impact. Notwithstanding the Dockyard and Colewort Barracks, the Royal Portsmouth Hospital on Commercial Road was hit badly. Its Casualty Block – already full of casualties from elsewhere – was struck killing nine people. Fires then subsequently spread across the administration block.

Ministry of Home Security Bomb Census Mapping.
Portsmouth Dockyard Bomb Map.

Residential areas of the city were also hit, particularly in those areas surrounding the docks and city centre. Moreover, transport infrastructure suffered. Portsmouth Town Station – now Portsmouth & Southsea – sustained some damage8.

After 1941, the raids on Portsmouth became more infrequent, and they were never as severe as those of 1940 and 1941. The raid of 15 August 1943 was perhaps one exception where at least 22 HE bombs caused a fair degree of damage across central parts of the city.

Furthermore, the city saw two V-1 pilotless aircraft bombs fall at Locksway Road and Newcomen Road. The latter incident killed 15 and hospitalised 829.

Damage at Dunbar Road, Eastney – 19th August, 1942.
Aerial image showing an air raid on Portsmouth – 24th August, 1940.

Can UXO still pose a risk to construction projects in Portsmouth?

The primary potential risk from UXO in Portsmouth is from items of German air-delivered ordnance which failed to function as designed. Approximately 10% of munitions deployed during WWII failed to detonate, and whilst efforts were made during, and after the war to locate and make UXBs safe, not all items were discovered.

This is evidenced by the regular, on-going discoveries of UXO during construction-related intrusive ground works across the UK – not just in Portsmouth.

Occasionally items of British explosive ordnance are also encountered – especially in more peripheral areas of the city, and areas historically utilised by the military such as a number of the parks, Portsdown Hill, and harbour areas.

I am about to start a project in Portsmouth, what should I do?

Developers and ground workers should consider this potential before intrusive works are planned, through either a Preliminary UXO Risk Assessment or Detailed UXO Risk Assessment. This is the first stage in our UXO risk mitigation strategy and should be undertaken as early in a project lifecycle as possible in accordance with CIRIA C681 guidelines.

It is important that where a viable risk is identified, it is effectively and appropriately mitigated to reduce the risk to as low as reasonably practicable (ALARP). However, it is equally important that UXO risk mitigation measures are not implemented when they are not needed.

While there is certainly potential to encounter UXO during construction projects in Portsmouth, it does not mean that UXO will pose a risk to all projects. Just because a site is located in Portsmouth does not mean there is automatically a ‘high’ risk of encountering UXO. It really does depend on the specific location of the site being developed.

A well-researched UXO Risk Assessment will take into account location specific factors – was the actual site footprint affected by bombing, what damage was sustained, what was the site used for, how much would it have been accessed, what were the ground conditions present etc.

It should also consider what has happened post-war – how much development has occurred, to what depths have excavations taken place and so on. This will allow an assessment of the likelihood that UXO could have fallen on site, gone unnoticed and potentially still remain in situ.

Recent UXO discoveries in Portsmouth

Construction work has previously unearthed both German air delivered ordnance, anti-aircraft projectiles used to defend the city, and other items of UXO, with the news articles below highlighting multiple recent UXO finds across the Portsmouth area.

Roads were closed after an unexploded bomb was found washed up on the beach at Southsea (near Portsmouth) in 2020 – read more here: https://www.portsmouth.co.uk/news/transport/road-reopens-after-unexploded-bomb-washes-up-on-the-beach-in-southsea-2520657

In 2019 a metal detectorist found some chemical Mortar rounds at Farlington Marshes in Portsmouth – read more here: https://www.portsmouth.co.uk/news/people/metal-detectorist-finds-chemical-mortar-rounds-at-farlington-marshes-in-portsmouth-1351972

A World War Two bomb containing 290lb (131kg) of high explosives was found in Portsmouth harbour in 2017 – read more here: https://www.bbc.co.uk/news/uk-england-hampshire-39049048

The Royal Navy detonated a WW2 bomb which was found in Portsmouth Harbour in 2016 – read more here: https://news.sky.com/story/evacuation-as-unexploded-ww2-bomb-found-in-portsmouth-harbour-10659246

All of these incidents were promptly investigated by the Police and/or local bomb disposal experts to minimise the risk, and avoid any potential damage to surrounding buildings and local infrastructure.


1William G. Easthope ed., Smitten City: The Story of Portsmouth under Blitz (Portsmouth: Portsmouth and Sunderland Newspapers, Ltd., 1981), p. 5.


3William G. Easthope ed., Smitten City: The Story of Portsmouth under Blitz (Portsmouth: Portsmouth and Sunderland Newspapers, Ltd., 1981), p. 5.



6Nigel Peake, City at War: A Pictorial Memento of Portsmouth, Gosport, Fareham, Havant and Chichester during World War II (Portsmouth: Milestone, 1986), p. 48.

7Nigel Peake, City at War: A Pictorial Memento of Portsmouth, Gosport, Fareham, Havant and Chichester during World War II (Portsmouth: Milestone, 1986), p. 49.


9William G. Easthope ed., Smitten City: The Story of Portsmouth under Blitz (Portsmouth: Portsmouth and Sunderland Newspapers, Ltd., 1981), p. 62.

Contact Us

* indicates required fields

This field is for validation purposes and should be left unchanged.