East German autobahns were used primarily for GDR military traffic and for state-owned farming or manufacturing vehicles. The speed limit on the GDR autobahns was 100 kilometres per hour (62 mph); however, lower speed limits were frequently encountered due to poor or quickly changing road conditions. The speed limits on the GDR autobahns were rigorously enforced by the Volkspolizei, whose patrol cars were frequently found hiding under camouflage tarpaulins waiting for speeders.