A location determination system includes one or more processors configured to determine a location of a vehicle system based on output from a location determination system onboard the vehicle system. The one or more processors also are configured to determine whether the location of the vehicle system as determined by the location determination system is accurate based on one or more of performance of the vehicle system, communication between two or more vehicles in the vehicle system, one or more other locations determined by one or more other location determination systems onboard the vehicle system, and/or operation of a brake system of the vehicle system.