WWII Air Raids on Gibraltar: History, Impact, and UXO Risks
During World War II, Gibraltar played an indispensable role in the British military strategy. Its unique geographic location at the southern tip of the Iberian Peninsula made it a vital naval base controlling access to the Mediterranean Sea. Gibraltar served as a crucial foothold for the Allies, providing strategic command centres, supply hubs, and a key position for naval and air operations. This made it both a heavily fortified stronghold and a frequent target for enemy military operations.
Gibraltar’s Strategic Significance
As a fortress and harbour, Gibraltar was critical for Allied operations in the Atlantic and Mediterranean Theatres. It controlled naval traffic through the Strait of Gibraltar, ensuring supply chains remained open. The Royal Navy’s ‘Force H,’ based in Gibraltar, played a pivotal role in maintaining naval superiority and escorting relief convoys to and from the besieged island of Malta.
In 1942, Gibraltar gained even greater prominence when it became the headquarters for General Dwight D. Eisenhower as he coordinated Operation Torch, the Allied invasion of North Africa. Eisenhower later credited Gibraltar as a key enabler of this campaign, stating, “Britain’s Gibraltar made possible the invasion of North-West Africa.”
Given this strategic importance, Nazi Germany devised Operation Felix, a plan to seize Gibraltar by passing through Spain. However, the cooperation of Spanish leader Francisco Franco was crucial for this operation, and his reluctance led to its abandonment. Instead, Gibraltar faced significant threats from air and sea attacks throughout the war.

Vichy French Air Raids
After the fall of France in 1940, the country was separated into two. The northern and western regions came under direct German occupation, while the eastern and southern areas were governed by the French Vichy regime, which declared neutrality. However, tensions with Britain escalated after Operation Catapult – a British attack on French naval forces in Mers El Kébir, in French Algeria – designed to prevent French ships from falling into German hands. This led to retaliatory air raids by the Vichy French Air Force, which had a large number of aircraft stationed in North Africa, well within range of Gibraltar.
The first air raid on Gibraltar occurred on 18th July 1940. While this attack caused casualties, it inflicted minimal damage. Reports suggest the bombing may have been deliberately restrained, with many bombs being dropped short, in the sea, intentionally (although, it is not possible to substantiate this claim). Larger raids followed on 24th and 25th September 1940, during which over 65,000 kilograms of bombs were dropped. The armed trawler HMS Stella Sirius was sunk, and civilian lives were lost. After these attacks, no further raids were carried out by the Vichy French.

Italian Bombing Campaigns
The Italian Air Force also targeted Gibraltar, launching long-range bombing missions from their nearest airfield in Sardinia, approximately 1,300 kilometres away. Their first raid occurred on 17th July 1940, using Savoia-Marchetti S.M.82 aircraft chosen for their extended range rather than bombing capabilities. They released their 4,000kg bombload with little response from anti-aircraft defences. The results of this air raid are unknown, as they were not observed by the Italian bombers, and the British did not publicly acknowledge the attack. Despite multiple missions by the same three aircraft throughout 1940 and 1941, their impact was minimal, and the campaign was paused due to operational demands elsewhere.
In 1942, Italy’s Piaggio P.108B heavy bombers were deployed in five raids on Gibraltar. The largest occurred on 28th June 1942, with four bombers dropping 66 100-kilogram bombs and six 250-kilogram bombs. However, once again British records do not provide detailed accounts of the damage caused.
By 1943, the Italian Air Force shifted tactics, targeting British ships in Gibraltar’s harbour with aerial torpedoes. The final and most notable attack in June 1944 involved nine bombers reportedly sinking six ships. This claim, however, was denied by British authorities.

Frogman Attacks
While aerial campaigns garnered attention, some of the most effective attacks on Gibraltar came from the Italian Navy’s Decima Flottiglia MAS, an elite unit specialising in underwater sabotage. Using manned torpedoes and explosive motorboats, these “frogmen” managed to sink or disable 20 merchant ships and five warships, totalling approximately 224,000 tonnes of shipping. These included the sinking of battleships HMS Queen Elizabeth and HMS Valiant.
The frogmen would use small manned torpedoes to sail close to British ships and attach ‘Limpet mines’. These are a type of naval mine magnetically attached to the hull of the targeted ship, usually set off by a time fuse. The frogmen could then depart the area, leaving little to no evidence of their presence.
Operating from a Spanish villa near Gibraltar initially, the frogmen faced challenges from British harbour defences, including patrol boats, searchlights, and submarine netting. They later relocated to the Olterra, an Italian merchant ship moored across the bay. The Italian frogmen discreetly replaced the crew with divers and engineers, building a workshop on the lower decks to construct and repair manned torpedoes. At the base of the ship, six feet under the water, a door was cut to allow the torpedoes to be launched to devastating effect. The British did not find out where the attacks were being launched from until the end of the war.
“Everyone has the jitters, seeing objects swimming about at night, and hearing movements on ships’ bottoms. It must stop!” – Admiral Sir Andrew Cunningham, Commander in Chief of Britain’s Mediterranean Fleet.
The Legacy of WWII in Gibraltar
Although Gibraltar’s WWII history is often overshadowed by larger campaigns, its role highlights the intricate political dynamics of the war and the contributions of smaller, strategic locations. Gibraltar’s story also underscores the global nature of the conflict, where battles played out across diverse theatres.
One enduring legacy of WWII in Gibraltar is the persistent risk of unexploded ordnance (UXO). This was made prevalent during a land reclamation project in Gibraltar Harbour in 1989, when sand dredged from Europe Point was found to contain over 1,000 UXO items, roughly a quarter of which were still live. Most were WWII-era munitions, though some dated back even further.


UXO Risks and Mitigation
Modern Gibraltar stands as a testament to resilience and adaptability. Its strategic importance and military history have left a tangible legacy, from the iconic Rock of Gibraltar to the remnants of its WWII defences. These sites, along with the stories of those who defended Gibraltar, serve as a reminder of the sacrifices and challenges of wartime.
The discovery of UXO in Gibraltar highlights the long-lasting impacts of WWII bombings. These remnants pose significant risks to construction, development, and public safety. Brimstone UXO specialises in managing such risks, providing comprehensive risk assessments, UXO surveys, and on-site support services to ensure safety during redevelopment projects.
For any construction or development projects in Gibraltar or other areas with a history of conflict, Brimstone UXO offers unmatched expertise in mitigating UXO risks. Get in touch with our Commercial Team today to ensure your project’s safety and success.
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