Example highway detection systems and methods are described. In one implementation, a method receives data from a vehicle data bus in a first vehicle and detects a speed of the first vehicle based on the received data. The method also determines a speed of an oncoming vehicle and a lateral distance between the first vehicle and the oncoming vehicle based on the received data. One or more processors determine whether the first vehicle is driving on a highway based on the speed of the first vehicle, the speed of the oncoming vehicle, and the lateral distance between the first vehicle and the oncoming vehicle.