Berlin Tegel Airport eminent aerospace engineers, which included German rocket pioneer Wernher von Braun. In 1937, the rocket pioneers left Tegel in favour of the secret Peenemünde army research centre. During World War II, the area served once again as a military training area, mostly for Flak troops. It was destroyed in Allied air raids. Plans for converting the area into allotment gardens were shelved due to the Berlin Blockade, which began on 24 June 1948. In the ensuing US-led Berlin Airlift, it quickly turned out that Berlin's existing main airport at Tempelhof was not big enough to accommodate all relief aircraft. As
Billy Bishop Toronto City Airport time, the island airport site was to become the site of the "Harbor City" residential development, although a replacement for the island airport had not been agreed upon. A 1969 proposal to build a new airport by the new headland was met with opposition from local residents and Toronto City Councillors and was dropped. With plans uncertain, the Government of Canada requested that the Harbour Commission continue to operate the airport as is in the interim. In 1972, the "Harbor City" project died when the governments of Canada and Ontario proposed to build a new major airport in Pickering, Ontario.