Heading east on Columbia Pike, at S. Rolph St, at the exit ramp to I-395 (just up the hill from the Pentagon and Navy Annex); police use LIDAR at the bottom of a 200 ft drop in about 1/4 mile along a 4 lane main artery leading to the Pentagon. The speed limit is 30 MPH. Even coasting you have to ride your brake all the way to the bottom of this 5-7% grade or you will dramatically pick up speed. Also, to safely merge with freeway traffic at the entrance ramp (where they set up LIDAR at the corner of Rolph St) you need to go at least 40 MPH to establish a safe merge speed. Police are particularly prevalent around the last week of the month. An officer will hand-hold a lidar "gun," and he or she usually has chase cars at the ready on the side streets. The fines are the highest in the Nation (as of July 1st). VA resident can receive $3550 penalty for 15 MPH over. If speed is less than 20 MPH over it is an "infraction" and you do not have typical defendant "rights." For example, you have no right of "discovery" because it is not "criminal." Barriers to appeal are very steep in Virginia. I classify Arlington traffic courts as "kangaroo," due to the steep barriers to appeal and absence of a prosecutor in court (the judge "acts" as prosecutor), and no rights of discovery (to check on equipment calibration).