Kocaelispor

Founded on 24 April 1966 through the merger of three Izmit clubs, Bacspor, Izmit Genclik and Doganspor, Kocaelispor represent Izmit and the wider Kocaeli province on the Gulf of Izmit. The green-and-black team are nicknamed Korfez, the Gulf, a name echoed by the outline of the gulf on their crest. Their home is the Kocaeli Stadium, opened in 2018 to replace the Izmit Ismetpasa Stadium, the club's ground for more than four decades.

Kocaelispor won the Turkish Cup in 1997 and 2002, and their best league finish of fourth in 1992-93 earned the club's first European campaign, in the UEFA Cup. They have also won the second tier four times, in 1979-80, 1991-92, 2007-08 and 2024-25. After financial collapse the club fell into the amateur leagues in 2014, then climbed back step by step, winning a fourth-tier title in 2019-20 and the 2022-23 TFF Second League Red Group, before regaining their Super Lig place in 2025, sixteen years after their previous top-flight season.