Abstract
The road environment can affect driver speed choice through influencing both the driver’s perception of their current speed, and the speed that they think is appropriate for the road. These influences and their effects on speed can therefore affect crash rates. This report reviews the influence of various factors within the road environment, including the geometry of the road, the roadside environment, explicit information from road signs and markings, and temporary factors such as lighting conditions and the presence of other road users. The review also covers how these environmental factors interact with other factors related to the driver and the vehicle. The concept of the ‘self explaining road’ is also discussed. (Author/publisher)