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April 20, 2008

Driving on the Other Side

I popped over the pond for a spot of teaching in London this week, and right now I'm relaxing in the British Airways departure lounge at Heathrow, which has a bunch of free computers (about half of which actually have the magic combination of a mouse that works and an Internet connection that works).

I rented a car while I was here, figuring it would be entertaining (never haven driven on the proper side of the road before). I was concerned about remembering to turn into the correct side of the road, but that actually wasn't a problem--having the steering wheel on the other side was enough to remind me. I did have a few minor things that kept happening:

  • I would drift a bit to the left of the lane--not into the next lane, but just a bit, I assume trying to compensate for a subconscious feeling that my body was in the wrong place.
  • I kept reaching for the seatbelt on the wrong side of my body.
  • When I wanted to in the rearview mirror, I always looked to me right, then wondered why the view out the side mirror wasn't what I was expecting.

A bigger problem was how narrow the roads were. On the way from my hotel to the training site I crossed the Chertsey Bridge, which was spot-on lovely, but was built in the 1780s and, as somebody put it, is wide enough for a horse and buggy to pass in either direction. Which makes it a bit tight if a lorry and a motorbus try to pass, or even two cars, if one of them is driven by an expat American trying to find second gear on his car.

The narrowness also made it hard to navigate because you couldn't stop for a second to look at a map without risking a head-on collision (not that such map-checking behavior is advised anyway). And it's a bit hard to navigate in general because street signs are a bit rare and the names change often anyway, so you have to follow the numbered roads, which follow more logical paths from town-to-town. But if you miscount at a roundabout and head off in the wrong direction, it can be very hard to figure out where you are, especially since the road numbers are only signed at roundabout exits. Furthermore at any given time there was some annoyed driver riding my bumper (the roads seem to alternate narrow and less narrow spots, so I think people hustle through the narrow spots to minimize their time spent in them). I wound up feeling a bit stressed most of the time I was driving, which I have not felt before, even in unfamiliar locations. On the first day I faced an oncoming bus on a narrow street, and had no choice but to put two wheels up on the opposing sidewalk, leaving me inches from the stone wall that conveniently bordered the road, for maximum claustrophobic effect. Nobody seemed to put out by all this, in fact there must be some unwritten rules on when you park your car half on the sidewalk and when you don't.

All-in-all I did enjoy driving in England. By the third day I knew where I was going and was passing bikers in front of oncoming traffic just like a seasoned Brit. And today I managed to make it back to the Avis rental return with the car and myself intact. The correct answer to all this might be "rent a GPS for the car", but that wouldn't be much fun, now would it?

Posted by AdamBa at April 20, 2008 06:04 AM

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My problem with driving in the UK wasnt so much that i was on the "wrong" side of the road, it was that I was on the wrong side of the CAR...it was very confusing.

Posted by: King of the Geeks at April 20, 2008 08:01 AM


I'm English, and I love the way you think our roads are tight... If you ventured into the villages, THAT's where it gets tight. Single-lane windy tracks with just the occasional lay-by which allow for 2-directional traffic flow. That's fun =]

Oh and your 2 wheels were on a pavement, not a sidewalk :P

Posted by: huckle at April 20, 2008 05:04 PM

And how many times did you walk up to the passenger side door instead of the driver side?

The "logical" road numbering in the UK works well for that type of road layout which is more of an arbitrary graph than the typical US grid system. Routes through an arbitrary graph can be much more efficiently described using "logical" connections and way points, however routes through a regular grid are more efficiently described using a set of physical connections (street names + compass direction).

BTW, the secret to getting back on track if you take a wrong turn in the UK is to look for the road name in parentheses on a sign, this indicates that the road you are seeking can be reached by going down this other road. The other trick is to look at sign posts at intersections that are pointing in the direction that are you are currently traveling as that will tell you what road you are currently on. For example as you pass a T junction (where you are continuing straight ahead and not turning) twist your head 90 degrees and read the sign pointing in the direction that you are traveling, it will tell you what road you are on.

And yes, the correct answer to your stress is to rent or buy a GPS (you can buy UK maps for $80 that can be downloaded into the basic $150 TomTom device that comes with US maps pre-loaded).

Posted by: Andrew at April 22, 2008 03:14 PM

I drove for a month around England and Scotland in 1967. I had less trouble driving than walking, since those skills (look left) were ingrained much earlier than driving. Anyway, being on the wrong side of the car kept me alert. One thing that impressed me was how well traffic circles worked. They had become anathema to US traffic engineers.

Three years later, I lived for a year in a small city in Switzerland (Fribourg/Freiburg). It was large enough to have a traffic circle in front of the railroad station and it became total gridlock in every rush hour.

So what was the difference? Why did they work so well in Britain and so badly in Switzerland? Eventually I figured it out. Both countries were using the "priority to the right" rule. A car coming to an intersection had priority over a car entering from the left and had to yield to a car on the right. The way this worked in Britain was that cars on the circle had precedence while in Swizerland the cars entering the circle had precedence over the ones already there, which led to gridlock and nothing moving. They had to assign a cop to deal with the resultant mess in Fribourg. Every morning and every afternoon.

The circles in Britain would tend to have a steady stream, say in the E-W direction until block by a car wanting to go three quarters of the way round, which would block them and then it would switch to N-S until they were blocked by right-turning cars and so on. An electronics engineer would call it an unstable multivibrator.

The canton of Fribourg (and maybe the rest of Switzerland) have now changed their traffic codes so that cars on a circle always have priority over cars wanting to enter. Unfortunately, the circle that I was familiar with has sufficiently increased traffic that they have added traffic lights and I don't know how well it would work without them. Presumably not well enough or they wouldn't have the signals. But the many circles out of the town do work smoothly.

Posted by: marble chair at April 24, 2008 06:25 AM

Did you have a manual or an automatic? It took me a while to get used to reaching for the shifter with my left hand with a manual. Fortunately, the pedals are arranged in the same way; that would have been one difference too many, I think.

As far as traffic circles and roundabouts, it's now well understood that circles where the entering traffic has priority lock up very easily, whereas circles where entering traffic yields can handle some pretty heavy volumes (even as high as 20,000-30,000 cars per day). Logically, the yield on entry option works better (since the people stopping can queue back along their road, as opposed to queuing in the circle where there is limited space), and I've always been surprised that in many places (including the US), the yield in the circle approach was the standard for many years. There has been a recent renaissance in the US for "circular intersections," although they are still pretty controversial. NJ has gone through much work to get rid of all of their traffic circles, but is not thinking about installing some modern roundabouts in other locations.

Posted by: JEB at April 24, 2008 06:37 PM

Standard shift. Actually, I misspoke. It was in '64 that I drove for a month. The fact that I was shifting with the left hand didn't bother me particularly. I had once before test-drove an Isetta with left-hand shift, a small lever on the driver-side window (the door was in front). In '70, I drove a in London for a few days. The latter was a left-hand drive car and even so it didn't bother me much. Then I went on to drive it for 16 months in Switzerland before bringing it home.

It is amazing how long it took traffic engineers to figure out that the cars on the circle should have priority. It took me about ten minutes to see why it worked in London and the opposite failed so spectacularly in Switzerland. My Swiss friend told me that there was a publicity campaign for months before they actually made the switch.

Posted by: marble chair at April 25, 2008 10:31 AM

I find the biggest hazard conditions when switching driving sides (in my case either USA->Aust or vv depending on where I'm living at the time) are the following:

+ nighttime - there are less visual cues, esp in unlit areas

+ exiting one way streets - very simple to turn on to the wrong side of the street if there isn't any traffic around

+ jetlag/tired/first day or two - the combination of jetlag, visiting friends and not sleeping and not having driven much yet can be pretty powerful

Hence one memorable evening when all 3 came together: after dark, soon after hopping off the plane from USA, visiting some friends, when I came out of a one way street, turned on to the wrong side of the ride and subsequently got very lucky and saw the headlights approaching my side of the ride in time to move quickly over to the correct side before they hit me!

Posted by: mikemee at May 23, 2008 11:14 PM