Kocaeli may refer to:
*
Sanjak of Kocaeli
The Sanjak of Kocaeli was a second-level Ottoman province (''sanjak'' or '' liva'') with capital at Iznikmid/Izmid (Byzantine Nicomedia, modern Izmit).
History
Kocaeli derives its name from Akça Khodja, an Ottoman Turkish warleader who began ...
, an Ottoman province
*
Kocaeli Province
Kocaeli Province ( tr, Kocaeli ili, ) is a province of Turkey and one of only three not to have the same official name as its capital, İzmit, which is thus also sometimes called Kocaeli. The province is the successor of the Ottoman-era Sanjak ...
, Turkey
*Kocaeli, an alternative name for
İzmit
İzmit () is a district and the central district of Kocaeli province, Turkey. It is located at the Gulf of İzmit in the Sea of Marmara, about east of Istanbul, on the northwestern part of Anatolia.
As of the last 31/12/2019 estimation, the ...
*
Kocaeli Peninsula
The Kocaeli Peninsula ( tr, Kocaeli Yarımadası) lies in the northwest corner of Anatolia, Turkey, separating the Black Sea and the Sea of Marmara on the Asian side of the strait of Bosphorus. Approximately one-third of Istanbul, one of the most ...
, the peninsula at the north west point of Anatolia
*
Kocaeli, İvrindi, a village
{{place name disambiguation
