1. A method comprising: receiving, by a computing device, movement data that is indicative of movement of a plurality of vehicles through an intersection, wherein the movement data comprises for each respective vehicle data indicative of the respective vehicle's position as a function of time for multiple instances of time and the respective vehicle's velocity as a function of time for the multiple instances of time; detecting a pattern in a distribution of velocities of the plurality of vehicles within a threshold distance of the intersection using the computing device; determining, based at least upon a presence of decreasing velocities and subsequent increasing velocities within the pattern, that the distribution of velocities is indicative of a presence of a probable traffic control for the intersection; and storing an indication of the probable traffic control for the intersection in a database.