Kartepe (literally Snowy hill referring to mountains to the south) is situated at 40°44′N 29°58′E / 40.733°N 29.967°E / 40.733; 29.967 to the east of the Gulf of İzmit.

Being a part of industrial area the population increased and in 1970 it was declared a seat of township.

In 2008 it was merged to nearby towns, renamed as Kartepe and became a district center of Kocaeli Province.

[5] Cengiz Topel Naval Air Station is located in the district.

Although Kartepe is founded in the low plains the mountains at the south serve as winter sports complex for nearby Istanbul citizens.