 During the gold rush, Geelong experienced a brief boom as the main port to the rich goldfields of the Ballarat district.The city then diversified into manufacturing, and during the 1860s, it became one of the largest manufacturing centres in Australia with its wool mills, ropeworks, and paper mills.It was proclaimed a city in 1910, with industrial growth from this time until the 1960s establishing the city as a manufacturing centre for the state, and the population grew to over 100,000 by the mid-1960s.