If it was up to the cops, they would patrol this partial area 24/7, but that would cause too many traffic backups. Here is the deal: If you are going East on route 7 (Broad st.) just a few dozen yards east of Haycock St, you are now in Falls Church city vs. Fairfax county. There is no sign, but if you look on the map it is so. The Falls Church cops generally hide just past this line and give out tickets fairy easily. The reason is that just a few hundred yards to the west on route 7, the speed limit is 35 mph, but then it becomes 25 mph. Now this is clearly posted and the regular commuter is well aware of this, but the visitors get caught fairly regularly. A few more circumstances are in favor of the cops: The interstate 66 ramp is a huge downhill ramp that dumps you out in the 35 mph zone, just to have it become 25 mph in a few seconds of driving. Also, route 7 (broad st.) is a 4-lane road, adding to the illusion of a higher speed, and its going downhill into Falls Church. The cops generally hide just past the Long John Silvers restaurant.