In most cities, mounted patrols declined in the mid-1940s due largely to the termination of the U.S. Calvary and the advent of the motorcycle; however, in the early 1970s, a resurgence of mounted units began, and now the number of municipal units has grown to more than 200 nationwide. Advantages of a mounted patrol over other patrol units are as a deterrent factor for criminals on foot, maneuverability, the ability to move among crowds, ability to go into areas inaccessible to motor vehicles, and the vantage point of height that permits seeing events as they occur and being seen by citizens who are seeking help. Training programs for mounted patrols vary across the Nation. In San Diego, for example, trainees are required to complete a 5-week, 200-hour training course, in which they are instructed in basic equestrian skills, and mob and riot control. Applicants must have been on the force for a minimum of 3 years. The New York City Mounted Division, which is the largest such unit in the country (120 horses), requires a 12-week training period. Officers must also have been on the force a minimum of 5 years before they can apply for the assignment. Throughout the Nation, most police horses are acquired as donations. The horses must have the temperament and the training not to bolt at loud, sudden noises; being approached by dogs; or being in crowds. Most of the officers who join a mounted unit do so because of their love of horses.