Gebze () is a working-class district and one of the municipalities in Kocaeli Province, Turkey. Its area is 418 km<sup>2</sup>, and its population is 407,019 (2022). It is situated 65 km (30 mi) southeast of Istanbul, on the Gulf of Izmit, the eastern arm of the Sea of Marmara. Gebze is the largest district by population size in the province as of 2022, exceeding ðzmit, the provincial capital. Its population consists of a colossal working class, one of the largest in Turkey, as it hosts 10 industrial parks, in which hosts 1,384 companies and over 130,000 people are employed.
The district of Gebze is located in the western portion of Kocaeli Province; with neighbors Körfez to the east; Pendik, Tuzla and à Âile in Istanbul to the northwest, west and north respectively; ÃÂayñrova and Darñca to the southwest and Dilovasñ to the southeast.
There are 40 neighbourhoods in Gebze District:
The northern terminus of Osman Gazi Bridge falls within this area; the construction â having a total length of 4 kilometers (with a 1,688-meter main span) â bridges the Sea of Marmara from Kababurun to Dilburnu. The Gebze Metro began construction in 2018 for a 2026 opening. The Marmaray intercontinental commuter rail line connects Gebze to the European side of Istanbul.
Gebze is twinned with: