In 1941, during the
Second World War, the
Royal Navy established a base ("Port T"). An isolated island base with a safe, deep anchorage in a suitably strategic position was required, and Addu met the requirements. Once available, its facilities were used extensively by the Fleet. Royal Navy engineers landed in August 1941 from
HMS Guardian to clear and construct airstrips on Gan for the
Fleet Air Arm. In the interim,
Catalina and
Sunderland flying boats operated from jetties on the northern, sheltered side of Gan. Large oil tanks were built on Gan, and on Hitaddu Island on the western edge of the atoll; vital elements for a naval base. These were visible from a long distances at sea, but this was unavoidable, given the atoll's low profile. Ship's supplies for the fleet were provided from a pair of Australian refrigerated ships,
Changte and
Taiping that included Addu in a number of bases that they serviced regularly. Three times these ships replenished forty or more ships of the Eastern Fleet. Several large
Australian Imperial Force troop convoys also refueled at Addu on their way from
Aden to
Fremantle, Western Australia. The six major islands were garrisoned by the 1st
Royal Marine Coast Defence Regiment, manning shore batteries and anti-aircraft guns. To facilitate the defence, causeways were built connecting the western islands of Gan, Eyehook (Abuhera),
Maradhoo and
Hithadhoo and, much later in the war, they were linked by a
light railway. Addu was an unpopular posting due to the hot, humid climate, lack of recreational facilities and lack of socialising with the local population. The
Japanese remained unaware of the base's existence until their plans for expansion in
South-east Asia had come to nothing, even during their carrier raids in the
Indian Ocean in April 1942. Later in the war, submarine reconnaissance established the base's existence. Despite openings into the lagoon being permanently closed by anti-submarine nets, the German
U-boat U-183 torpedoed the tanker
British Loyalty in March 1944 (she had been previously torpedoed and sunk at
Diego Suarez in May 1942, but was raised and towed to Addu for use as an oil storage vessel); this was a long-range shot from outside the atoll through a gap in the anti-torpedo nets. Although seriously damaged, the tanker did not sink. She was not fully repaired but kept as a
Ministry of War Transport Oil Fuel Storage Vessel. There was significant oil pollution after this incident and British personnel were used to clean the lagoon, but they were only partially successful. On 5 January 1946,
British Loyalty was scuttled southeast of Hithadhoo Island in the Addu Atoll lagoon. Despite the fact that she is still leaking oil, she has become a popular diving location. In 1957, the naval base was transferred to the
Royal Air Force. From 1957, during the
Cold War, it was used as an outpost as
RAF Gan. The base remained in intermittent service until 1976, when British Forces withdrew. From Gan Island several rockets of the
Kookaburra type were launched from a pad at 0°41' S and 73°9' E. Most of the employees who had experience working for the British military spoke fluent English. When the base at Gan was closed for good, they turned to the nascent tourism industry for employment. As a result, there was an influx of
Addu people to
Malé seeking employment in the nearby
resorts and also looking for education for their children. After the British military left, the airstrip was neglected and remained almost unused for many decades. Recently it has been developed into what is now
Gan International Airport and also has a
tourist resort,
Equator Village. ==Climate==