Highway 17 Southbound – radar enforcement between Summit Road and Scotts Valley – Highway Patrol with marked and at least two white unmarked cars – enforced much of the time, even late at night – best recommendation is to follow the speed limit, although it could be higher and still be safe. When an accident occurs, traffic is tied up for long period of times as there are no places to pull off the road in many places, and the highway is heavily traveled.