 It was originally bounded on the west by the Murrumbidgee River, on the east by the Shoalhaven River and on the north by the Yass River.A large area of the county was transferred to the Commonwealth government in 1909 in the Seat of Government Acceptance Act to make part of the Australian Capital Territory, along with land in Cowley County.Since then, the ACT border is now part of the western boundary.