AR 340 provides access to US 71 before trailing west into recently developed parts of Bella Vista.
The highway begins in west Bella Vista at Forest Hills Boulevard near the Northwest Arkansas Community College Bella Vista campus. AR 340 winds past numerous retirement communities and a few lakes on its way through the village. Approximately halfway along its length, AR 340 intersects US Route 71, which is a four-lane expressway. The interchange with US 71 is unusual, with long ramps on the northbound side and cramped southbound ramps. Traffic must exit US 71 and slow immediately to 20 mph (32 km/h) on a 180 degree curve before stopping and gaining access to AR 340.
The route was added to the state highway system on August 25, 1965. Described as the road from northeast of Hiwasse to the junction of Highway 94 at the Missouri state line, the routing has changed little since first designation.
^ abPlanning and Research Division (2010). "Arkansas Road Log Database" (Database). Arkansas State Highway and Transportation Department. Archived from the original on 23 June 2011. Retrieved June 9, 2011.