Nogometni Klub Čelik (English: Football Club Čelik) is a professional football club based in Zenica, Bosnia and Herzegovina. The name Čelik means "Steel" in Bosnian and it symbolizes the strength and power of the club and the city since Zenica is an industrial city well known in this part of Europe.
NK Čelik is one of the most prominent and successful football teams in Bosnia and Herzegovina being the only Bosnian club to win the national championship three times in a row – from 1994 to 1997. During the time of the former Yugoslavia, Čelik had played 17 seasons in the Yugoslav First League.
Čelik play their home games at the Bilino Polje stadium which is also the biggest stadium in the city. Over the years the club had changed four different stadiums settling at their current ground in 1972.
During the first few years of the club's existence, following World War II, Čelik's stadium was located roughly on the place of the current Bilino Polje stadium, close to the Bosna river. The ground was covered in clay, as was the practice of lower-level football grounds at the time. The stadium itself had one wooden stand which was built over time and the club often played in front of full capacity.
However, due to the increased popularity of the club and the need for a better surface, during the early 1950s the club moved to the nearby Stadion Blatuša which was located in the Blatuša neighborhood of Zenica. It was there that Čelik started its first run of successes when they had reached promotion to the Yugoslav First League in 1966 and won the Mitropa Cup in 1971 (the final was played on neutral ground in Gorizia, Italy).
Shortly after the first Mitropa Cup victory, plans were made for a new, modern stadium, built in place of Čelik's first stadium. The construction took 8 months to complete and it was officially opened on 4 October 1972 for the second leg of the 1972 Mitropa Cup final against Fiorentina which Čelik won 1–0 to claim their second title in a row. The attendance record of 35,000 still stands today due to the introduction of seats on the stadium over the years. The stadium went through a number of renovations and reconstructions, the most recent being in 2012.
From July to August 2012, the stadium went through another renovation process where the pitch had been changed and under-soil heating installed beneath. During the reconstruction, Čelik played two Bosnian Premier League matches as well as one Bosnian Cup match on the Stadion Kamberovića Polje, winning all of them. In the second part of the same season, the club played one more game there which ended in a draw.
The youth squads of Čelik usually play their games at the smaller stadium Kamberovića Polje.