Jaworzno is a city in southern Poland, located in the Silesian Voivodeship. It is the seat of Jaworzno County. The city has a population of 73,711 (2008) and an area of 69.5 km²..
The city was first mentioned in a Latin document of Diocese of Wrocław called "Liber fundationis episcopatus Vratislaviensis" from around 1305 as "item in Jaworzno". It meant that the city was not founded by the Bishopric of Wrocław, but was just a part of its lands.
The city was probably founded in the late 12th or early 13th century. It was one of the first settlements in the area, which belonged to the Duchy of Opole and Racibórz.
The first known owner of the city was Piotr Włostowic,