Nogometni Klub Celje (English: Celje Football Club), commonly referred to as NK Celje or simply Celje, is an association football club from Slovenia. They are based in Celje, Slovenia's third largest city. They play in First Slovenian League, 1.SNL. Together with Maribor and Gorica they are the only club that have participated in every season of the Slovenian PrvaLiga since its formation in 1991.
NK Celje was formed in 1919 as SK Celje. Soon after the World War II, in 1946, the club changed its name to NK Kladivar (expressionistic term in Slovene for a blacksmith). In 1964 they qualified for the Yugoslav Second League, where they played for two years in a row.
In 1992, year after Slovenia gained independence from Yugoslavia, the club again changed its name, this time to Publikum. They reached the finals of Slovenian Cup in 1993 and 1995, but lost on both occasions, having been beaten by Olimpija and Mura. In 2003, Celje was in a title race with Maribor until the very last, but in the end finished second and also lost Slovenian cup finals against Olimpija in the same year. Two years later in 2005 the club reached Slovenian cup finals for the third time and this time they finally lifted their first trophy, defeating Gorica 1–0 in front of their own fans at the Arena Petrol. Celje were also in the finals the next year, but lost to Koper after the penalty shoot-out.
For most of its early years, the club played at the Glazija Stadium, but moved to the Skalna Klet after merging with ŽŠD Celje in 1967. Since the stadium was in bad shape and could not meet UEFA stadia criteria, the club officials decided to build a new stadium and in 2003 the main stand of the new Arena Petrol stadium was built. The capacity at the time was 3,600 covered seats. After 2003, three new separate stands were build and when the last one opened in 2008, the stadium was completed. The current capacity of the stadium is 13,006 seats from which around 50% are covered. The old stadium is still used as a training facility for the club.
The club also has a smaller third training ground called Olimp, which was renovated in 2005 and is used as a training camp for youth squads of the club.