Korfez is a district in Kocaeli Province, Turkey, located on the eastern shore of the Gulf of İzmit, which is an inlet of the Sea of Marmara. Korfez is known for its industrial facilities, including petrochemical plants and factories. The district is also home to some residential areas and has a growing population. Korfez is an important transportation hub, with a highway and railway passing through the area. The district has a mix of industrial and residential areas, with some commercial and recreational facilities as well.