Morski Związkowy Klub Sportowy Arka Gdynia (Polish pronunciation: [ˈarka ˈɡdɨɲa]) is a Polish professional football club, based in Gdynia, Poland, that plays in the Polish Ekstraklasa. The club was founded as Klub Sportowy Gdynia in 1929.
The history of Arka dates back to 1929, when a group of workers of the Port of Gdynia founded Sports Club (Klub Sportowy, KS) Gdynia. In 1932, a new stadium of KS was opened at Polanka Redlowska. This location was used by the club until 2000. In 1934, Sports Club Kotwica (Anchor) was registered. Both team existed until 1939.
In 1949, Fishermen Sports Club (Rybacki Klub Sportowy) MIR was formed. Three years later, its name was changed into Klub Sportowy Kolejarz-Arka Gdynia. In 1953, the team for the first time won promotion to the third level of Polish football. In 1959, Arka’s U-19 became Polish runner-up, and in 1960, after a dramatic game vs. Hutnik Kraków, Arka won promotion to the Second Division.
In 1964, Arka merged with Doker Gdynia, to form Maritime United Sports Club (Morski Związkowy Klub Sportowy, MZKS) Gdynia. In 1972, its name was changed into Arka. Two years later Arka won promotion to the Ekstraklasa. Relegated after one year, Arka returned to the top level in 1976. In 1979 Arka, managed by Czesław Boguszewicz, became the first team from Polish Baltic Sea coast to win the Polish Cup. In the final game, which took place in Lublin, Arka beat Wisła Kraków 2–1. In its UEFA Cup Winners' Cup debut, Arka lost to Bulgarian side PFC Beroe Stara Zagora (3-2, 0-2).
In the 1980s and 1990s, Arka played either in the third or second division, with a number of promotions and relegations. In 2001, after six years in the third level, Arka again won promotion to the second division, and in 2005, the team returned to Ekstraklasa.
In 2011, the City of Gdynia completed the construction of a new stadium, located on Olimpijska Street. On February 19, 2011, in a friendly game to commemorate the opening of the stadium Arka tied 1-1 with Beroe Stara Zagora. That year, Arka Gdynia got relegated from the top level.