Tallinn Airport (IATA: TLL, ICAO: EETN) is the largest international airport in Estonia. The airport is also officially called Lennart Meri Tallinn Airport (Estonian: Lennart Meri Tallinna lennujaam) after the former president of Estonia Lennart Meri.

The airport is located 2.7 nautical miles (5.0 km; 3.1 mi) southeast of the city centre of Estonian capital Tallinn, on the eastern shore of Lake Ülemiste. It was previously known until 2009 as Tallinn Ülemiste Airport. The airport has a single asphalt/concrete runway, 08/26, that is 3,480 m × 45 m (11,417 ft × 148 ft) and large enough to handle wide-bodied aircraft such as the Boeing 747, six taxiways and seventeen terminal gates.

Prior to the establishment of the present airport in Ülemiste area, Lasnamäe Airfield was the primary airport of Tallinn, serving as a base for Aeronaut airline. After Aeronaut went bankrupt in 1928, air service was continued by Deruluft, which used Nehatu instead, 12 km (7.5 mi) from the centre of Tallinn. The first seaplane harbour on the shores of Lake Ülemiste was built 1928 to 1929 in order to serve Finnish seaplanes. The use of this harbour ended in World War II. On 26 March 1929 Riigikogu passed an expropriation act in order to establish a public airport. 10 ha (25 acres) of land was expropriated from Dvigatel joint-stock company and another 22 ha (54 acres) was expropriated from descendants of Vagner. 10 million sents were paid to land-owners as indemnity. Land leveling and renovation works took another 5 million sents.

The building of Tallinn Airport started on 16 November 1931, and the first test landing was commenced by captain Reissar piloting Estonian Air Force Avro 594 Avian, tail number 120. The airport was opened officially on 20 September 1936, although it had been operational a good while before the official opening - LOT Polish Airlines, which commenced its first passenger flight from Tallinn on 18 August 1932 with Fokker F.VIIb/3m from Lasnamäe Airfield, later relocated the flights to Tallinn Airport and in 1935 the airport had 6 arrivals and departures on average every day. In April 1935 a ramp for seaplanes was built on a shore of Lake Ülemiste, together with a small arch bridge and a customs office, which allowed seaplanes to be relocated from a sea port. The same year the airport administration building was erected, which also served initially as a waiting place for travellers. The total cost of the whole airport project, including the cost of building flight hangars, was 25 million sents.

As the very first runways had soft surface, it made them unavailable for takeoffs and landings during spring and autumn seasons. Therefore, only seaplanes stationed at Lake Ülemiste were able to carry out flights, and during winter months, it was possible to use the frozen surface of the lake as a runway for small airplanes. The concrete paved runways of the first stage, inaugurated together with the opening of the airport, were about 40 metres (130 ft) wide and 300 metres (980 ft) long. As they were arranged in a form of a triangle, they allowed takeoffs and landings in six directions. These were the first concrete-paved runway in Estonia, it was needed some 5,396 cubic metres (190,600 cu ft) of stone, 4,100 cubic metres (144,800 cu ft) of construction aggregate and 137 t (135 long tons; 151 short tons) of cement to construct them.

In addition, 3 km (1.9 mi) of pipeworks was laid for drainage purposes. Before World War II, Tallinn Airport had regular connections to abroad by at least Aerotransport (now part of the SAS Group), Deutsche Luft Hansa, LOT and the Finnish company Aero (now Finnair). On 5 April 1937 the Helsinki-Tallinn-Warsaw-Jerusalem route was inaugurated by Mr. Bobkowski, the assistant of the Polish Minister of Transport. The length of the route was 3,187-kilometre (1,721 nmi) and the journey time was 34 hours. Passengers and cargo numbers grew quickly, from 4,100 passengers and 6,730 kg (14,837 lb) of cargo in 1933 to 11,892 passengers and 14,726 kg (32,465 lb) of cargo in 1937. Preparation and design works for a new passenger terminal started in 1938. 14 various projects were submitted for the architectural contest of the new terminal building, with the one from the architect Artur Jürvetson winning the contest in February the same year. The construction costs were estimated at 300 thousand Estonian kroons. The first airplane of then the flag carrier of Estonia, AGO, arrived at Tallinn Airport on 5 October 1939, flying the route Dessau - Königsberg - Tallinn.

As Estonia was occupied by Soviet Union, on 22 July 1940 the order was made by Soviet occupation authorities to transfer the airport to Soviet Air Forces. All aircraft, which were at the airport at that time, including interned Polish Lockheed 14, two Junkers Ju 52 of AGO and PTO-4 trainer aircraft of Estonian Airclub, were relocated to Lasnamäe Airfield.

During the German occupation, regular international connections were announced on 16 October and already restored on 15 November 1941, when Deutsche Lufthansa and Aero O/Y started the route Helsinki-Tallinn-Riga-Königsberg-Berlin. From 1942 to 1944 Sonderstaffel Buschmann was based at Tallinn Airport.