Proclaimed a state highway in 1935, it was officially named as the Barton Highway in August 1954, signposted as National Route 25 two years later, fully sealed by 1960, and granted national highway status in 1974. The original purpose of the Yass-Canberra Road was to connect surrounding towns with the newly established national capital. Prior to the highway's establishment a series of trunk routes connected farming locations in the Yass Valley. Heading east from Yass, the Barton Highway originally commenced at a junction on the Hume Highway, near the historic Cooma Cottage, and east of the Yass River. Requiring traffic to make a righthand turn across a single lane of the Hume Highway, the highway commenced at this point and tracked generally south by southeast, through undulating hills to the village of and entering the Australian Capital Territory, going through the village and main street of, and meeting the Federal Highway at at a junction near Sullivans Creek on Mouat Street, adjacent to Lyneham High School and to the south of the Highway's current alignment. The first realignment occurred during the late 1970s, when the southern terminus of the highway was relocated north, to the north of the Yowani Country Club. In 1980 the village of Hall was bypassed; and during the early 1990s a dual carriageway was completed on the ACT section of the highway, between Hall and. A further section of dual carriageways was completed in December 2002, between Gungahlin Drive and the southern terminus with the Federal Highway. Between April 1993 and May 1995, as part of the Hume Highway bypass of Yass, a dual carriageway deviation of Barton Highway was constructed to connect the Barton Highway with the new route of the Hume Highway, north of Yass. The new route crosses the Yass River on twin bridges to the east of Cooma Cottage before terminating at the Hume Highway about northeast of Yass. The Gundaroo Drive/Barton Highway round-about is surrounded by a number of trees to the south of the intersection. The pine tree plantation was originally planted in the shape of a map of Australia
Murrumbateman bypass and staged duplication
The Barton Highway passes through farmlands and the NSW town of Murrumbateman. In October 2001 the Australian Government announced that they would bypass to the town to the east. A$20 million was set aside in the 2006 federal budget for planning and duplication costs associated with the bypass. The same year, the National Roads and Motorists' Association had named the Barton Highway as the worst highway on the Auslink National Network in New South Wales; accounting for three road fatalities annually. While of the highway are located in New South Wales, only of the NSW section are dual carriageway. Various NSW and Federal governments have committed funding towards improvements to the Barton Highway, including a bypass east of Murrumbateman and a staged duplication to create of dual carriageways. Construction work has not commenced.
