Kocaeli is a state in Turkey, mostly known by its district center, Izmit. The ancient name of this city is Nicomedia. Remains from Roman and Byzantine times may be seen here, including an ancient citadel and the Temple of Augustus.
The city of Izmit is mainly industrial with numerous industrial establishments surrounding the Gulf of Izmit. However, tourism is also an important moneymaker. Kartepe is a winter-sports resort that reaches a height of over 5200 ft. Kerpe and Kefken on the Black Sea coast have fine beaches, while Golcuk and Karamursel in the Gulf of Izmit are beautiful sea resorts. Lake Sapanca is another natural beauty. Another town of Kocaeli is Hereke, where top-notch Turkish carpets are produced. The artistic carpets of Ottoman palaces were woven here.