The Algerian 'Ligue Professionnelle 1'; known as 'Championnat National de Première Division' or 'Ligue 1' for short, and formerly known as the 'Championnat National 1', is the Algerian professional league for association football clubs.

It is the country's primary football competition and serves as the top division of the Algerian football league system. Ligue 1 is one of two divisions making up the 'Ligue de Football Professionnel', the other being 'Ligue Professionnelle 2'. The league is contested by 16 clubs, and it operates on a system of promotion and relegation with Ligue 2.

The league was created in 1962, when Algeria became an independent nation. Until 1950, only regional leagues (Algiers, Constantine, Oran) were contested. Some 'national' playoffs were played in the first decade of the 20th century, first in 1904. Between 1920 and 1956 the winners played off for the North African Championship, together with league winners from Morocco and Tunisia.

The teams play a double round-robin (a competition in which each contestant meets all other contestants in turn. A round-robin contrasts with an elimination tournament, in which participants are eliminated after a certain number of losses) competition. The final Top 2 qualify to the CAF (Confederation of African Football) Champions League, the 3rd place getter qualifies to the CAF Confederation Cup, alongside the Algerian Cup winner.

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