If you are a recent arrival to the D.C. area from Northern California, as I am, this is your fair warning: the rules of the road are different here!

These are some of the things I've noticed since I arrived from Marin County in December 1984 (and to those who say, "If he doesn't like it here, why doesn't he go back?" believe me, I'm trying): Driver Courtesy. I estimate that not more than five drivers out of 100 practice this, so don't take it for granted.

Red Lights. When someone actually stops at a red light, there are some drivers who will go around the offending light by going through service stations or supermarket parking lots. I even saw one recently practicing the "right-left-right" maneuver at the intersection of Gallows Road and Columbia Pike.

Slower Traffic Keep Right. Maryland has some of these signs posted on I-270 (but not many), but I have yet to see one in Northern Virginia, so don't expect drivers to move to the right so you can pass. Evidently, the term "fast lane" has a different meaning here.

Automobile Turn Signals. Drivers here use turn signals only as a last resort.

Overtaking Other Traffic. Don't expect people to get into a passing posture and actually pass the other car.

Entering Exit Lanes. Just because the driver in front of you has almost passed the exit itself, don't assume that he isn't going to take the exit.

Follow the Leader (a k a The Herding Instinct). Drivers here tend to do what other drivers do -- right or wrong. It isn't surprising to see a lane of traffic with six to 10 cars in it stopped at a traffic signal and an adjacent lane completely open. You might suspect that they are all in a funeral procession, but they don't have their headlights on.

MPG. Wrong, it's not miles per gallon. Several months ago, Regardie's magazine had on its cover the words "MONEY, POWER and GREED," which described the driving forces around D.C. It certainly reflected driving habits of the populace.

And now, a couple of things about pedestrians:

The Mystery Line. The reason for the big, broad line on the road near a traffic signal (and before the pedestrian crosswalk) appears to be a complete mystery to most folks around here. Shall I let you in on the secret? It is the STOP Line. It is the line before which one must stop his vehicle or be guilty of having run the red light. The placement of the line is meant to allow adequate space for crossing vehicles to pass safely.

Pedestrian Crosswalks. Do not assume when you blithely step out into a PED XING that cars will stop.

The motorists here are not necessarily any different from motorists anywhere; they are just more frustrated. The MPG syndrome (see above) and a large transient population contribute to the differences in traffic patterns between Marin County and Fairfax County.

Gov. Gerald Baliles has promised to do something about the traffic problems in Northern Virginia. He did impose a special gasoline tax to finance the improvements. But the only improvements this motorist has seen are a few "traffic-actuated" signal lights. In contrast, I have seen new traffic lights installed where traffic had been moving along reasonably well. What a place! -- Ernest P. Stokes