In an example, a method may read, at a first timestamp using a first reader device and a second reader device of a first vehicle, a first marker position from a first marker device located on a road segment at the first marker position and a second marker position from a second marker device located on the road segment at the second marker position that is different from the first marker position. The method may determine a vehicle position of the first vehicle on the road segment at the first timestamp based on the first marker position of the first marker device and the second marker position of the second marker device.