Navigation systems, methods and programs for a vehicle detect a number of travel lanes available for traveling in a direction that the vehicle is traveling. The systems, methods, and programs detect a lane in which the vehicle is currently located and determine a congestion degree for each of the available travel lanes. The systems, methods, and programs determine a degree of difficulty of turning right or left at a next intersection that the vehicle is approaching based on the detected number of available travel lanes, the detected lane in which the vehicle is currently located, and the detected congestion degree. The systems, methods, and programs select a travel route in accordance with the determined degree of difficulty and provide guidance information on the selected travel route.