Until its merger with the Wyong Shire in 2016, The City of Gosford covered an area of . Its administrative seat was located in Gosford, approximately north of Sydney and approximately south of Newcastle. The City was bounded to the east by the Tasman Sea, to the south by Broken Bay and the Hawkesbury River, to the west by the Great North Road where it encircled the Dharug National Park taking in the catchment area of the Mangrove Creek Dam, before heading south–east towards the coast, north of Forresters Beach.