The reference track is part of the Application Platform for Intelligent Mobility (AIM) large-scale research facility, operated by the German Aerospace Center (DLR) Institute of Transportation Systems. It serves as a testing ground for Car2X communications in urban environments and is used to test and evaluate cooperative driver assistance systems. Such investigations include those looking into communications between the vehicle and road infrastructure (such as traffic lights). Thanks to research into Car2X communication, traffic in towns and cities is predicted to become safer and more efficient in the long term. The information transmitted via Car2X allows the driver or driver assistance system to adjust their behaviour and drive with greater foresight in a more energy efficient manner. The reference track covers the entire Braunschweig inner city ring road, in different stages of development. The junctions are equipped with the latest communications technologies, enabling networking between vehicles and infrastructure components. In addition, information can be obtained from traffic lights and other road infrastructure, as well as being exchanged between vehicles.