Early years

On 11 October 1919, the Grand Council of Geneva approved the establishment of an "airfield" at Meyrin. A simple airfield was established in Cointrin, near the city of Geneva, covering an area of 54 hectares (130 acres). From 1926 to 1931, the airfield's wooden sheds were replaced by three concrete hangars. At the time, there was a small amount of air traffic, with Luft Hansa flying from Berlin to Barcelona via Halle, Leipzig, Geneva and Marseille. Swissair also flew the Geneva–Lyon–Paris route through a codesharing agreement with Air Union. By 1930, there were six airlines that flew to Geneva Airport on seven different routes.

1937 saw construction of the first concrete runway; it measured 405 by 21 metres (1,329 by 69 ft). In 1938, eight airlines were flying to Geneva: Swissair, KLM, Deutsche Luft Hansa, Air France, Malert (Hungary), AB Aerotransport (Sweden), Alpar (Switzerland) and Imperial Airways (UK).

During World War II, the Swiss authorities forbade all flights from Switzerland, but expansion of the airport led to increasing its area to 95 hectares (230 acres) and extending the main runway first to 1,000 by 50 metres (3,280 by 160 ft). A further 200 metres (660 ft) of runway was added near the end of the war as well as provision for future expansion to a length of 2,500 metres (8,200 ft).

As part of the Federal Government's post-war planning for the nation's airports, Geneva was identified as one of four main urban airports that were to form the first tier of that system. Cointrin was noted as being well suited for extension and did not require a triangular runway arrangement as the prevailing winds are very regularly along a single axis. Authorities agreed to a 2.3 million Swiss Francs project to build the first terminal in Geneva, and in 1946 the new terminal – which is today used as Terminal 2 – was ready for use, and the runway was enlarged once more to 2,000 m (6,600 ft). In 1947, the first service to New York started with a Swissair Douglas DC-4. On 17 July 1959, the first jet aircraft landed in Geneva, an SAS Caravelle, and it was followed, 11 years later, by a TWA Boeing 747 which landed in 1970.