Along Route 123, between the entrance to the Dulles Toll Road and Old Dominion Drive, is an area frequented by police cars. Since it is a 35 mph zone that is a divided 4-lane highway, most cars travel at ticketable speeds on this stretch, and cars often do get stopped and ticketed. But there is a police station right at the Lewinsville Road intersection in the middle of this stretch, so obviously there are police cars around often.