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Few drivers seem to have a good word for motorways these days, moaning about congestion on some of our more notorious stretches, the tedium of driving on them, and the frequency of roadworks. Yet motorways have allowed motorists to make a long journey in a time which would have seemed inconceivable 30 years ago.

Much of the rather morbid mystique associated with motorways can be blamed on the media, because a motorway accident is sufficiently catastrophic for television and newspapers to focus their attention on it. As a result, it is often forgotten that motorways have a lower accident record than other main roads. Since the chances of an accident on a motorway are much lower than one on a comparable non-motorway trunk road, it provides a safer route, as well as a quicker one, to your destination.

Speeds on motorways are such, however, that great discipline is required to use them safely. You must stick to the rules, and in doing so you might help to avoid some of the disasters which a few motorway hooligans seem determined to cause. You will encounter plenty of bad driving on motorways: the advice which follows will help you to make sure that your own driving is responsible and safe, even if others fail to meet the standard. The Institute's views on motorway driving, of course, follow the rules and guidelines described in the Highway Code, but to these basics can be added the wisdom gained from experience. Our advice is influenced by the comments we have obtained from the most professional of all professional drivers — the police patrol officers.

Motorways have two great advantages: they are one-way and there are no junctions, so you should not have someone coming towards you or nipping across in front of you. It is just possible, though, that one day in your driving life you may meet a driver who is dim enough to break these most fundamental rules. There have been incidents, some resulting in fatalities, of drivers making a U-turn through the central reservation after missing their exit. There have also been cases of drivers somehow managing to proceed along an exit slip road in the wrong direction and meet oncoming traffic when they reach the carriageway. If you should be unlucky enough to meet a driver such as this, we can only recommend that you take avoiding action, flash your headlights and blast your horn, and stop at the next emergency telephone (these are a mile apart) to inform the police.

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Before dealing with the techniques of advanced driving on motorways, some brief words are necessary about terminology. Some drivers describe the three lanes of a motorway as the 'slow', 'middle' and 'fast' lanes: this is misleading, since speed alone does not determine the use of lanes, and to describe a lane as 'fast' smacks of irresponsibility. More usual practice is to use the terms `inside', 'centre' and 'outside', but as more and more motorway sections with four lanes are being constructed this nomenclature is becoming outdated and could be confusing. The best way is the notation used by the police, and this is what we shall follow in this article. Each lane is simply given a number: therefore, lane 1 is the 'inside', lane 2 the 'centre' and lane 3 the 'outside', with lane 4 used where applicable.

Joining a motorway

When joining a motorway by a slip road your speed should match that of the traffic in lane 1. You should remain in lane 1 for at least half a mile before moving into lane 2.

The motorway slip road should be used to accelerate to a speed which matches that of the traffic in lane 1. Signal a right turn so that anyone in lane 1 will notice you, and will maybe move over to lane 2 to give you plenty of room. Your run along the stretch of the slip road adjoining the main carriageway should be timed so that you can slip neatly into place as soon as possible without losing speed, but keep a wary eye on the timid driver who may be slowing down at the end of the slip road to wait for a large gap in the traffic. In extreme cases, this kind of driver -who is as much of a menace to himself as to other road-users — may even stop at the end of the slip road, as if to give way.

You should remain in lane 1 for at least half a mile to adjust yourself to the speed and assess the traffic pattern behind you. If you are driving a car (rather than a lorry, or a car towing a caravan), your cruising speed will probably mean that you will spend a good proportion of your motorway journey in lane 2, so move over, after the usual mirror check and right turn signal, when it becomes necessary. Return to lane 1 whenever it is reasonably clear after overtaking manoeuvres have been completed. Lane 3 is not the fast lane which many people take it to be, so use it only for overtaking.

Motorway discipline

Your speed along a motorway should be one at which you, your passengers and the car feel comfortable, and one which is appropriate to weather conditions and traffic density - but it must not be over 70mph. You should not drive so unreasonably slowly along a motorway that you inconvenience other drivers coming up behind, but neither should you treat 70mph as an obligatory speed: 70mph is a limit, not a target. Travelling a few miles per hour under the limit will make little difference to your journey time.

If a motorist comes up behind travelling at more than 70mph, it is not your job to uphold the law. Baulking an overtaking driver, whether or not he is travelling at a legal speed, can be dangerous as well as discourteous, and the police would not thank you for it.

Lane discipline

Once you have settled into a steady cruising speed, glance in the mirror frequently so that you are constantly aware of all the vehicles around you. Maintain strict lane discipline, so that you are always in the appropriate lane for your speed and the traffic conditions. Poor lane discipline is one of the most common examples of bad driving on motorways, and it can occasionally play its part in an accident when it forces drivers unnecessarily into lane 3. Far too often on motorways you see more traffic travelling in lane 3 than in lanes 1 and 2. If there is a reasonable break in the traffic in lane 1, that is where you should be.

If you come up behind a 'lane hog' who fails to move over when there is plenty of space available, do not resort to the aggressive tactics which many drivers employ. Remember that the principles of good driving require you to maintain a proper braking distance, so never be tempted to force a slower vehicle aside by looming large in the driver's mirrors. Be patient and wait for the opportunity to overtake safely. Never overtake on the inside: as well as being a serious offence, this can be dangerous since no driver expects it to happen.

Keep your distance

Keeping a safe distance between you and the vehicle in front is even more important than good lane discipline. The importance of leaving room for seeing, reacting and braking has already been explained elsewhere in this book, but maintaining a safe distance is particularly relevant on a motorway. It is all too easy to close up on the vehicle ahead so that the distance between you is nothing like adequate in an emergency, so keep reminding yourself of this point. Drivers stopped by the police for driving extremely close, or 'tailgating', often use the excuse that they can see several vehicles ahead, but they are deluding themselves. This foolish attitude ignores all kinds of possibilities: the driver ahead might brake suddenly if he sees a piece of debris in the road, a vehicle from the opposing carriageway might crash through the central reservation, or the vehicle ahead might even suffer a tyre blow-out. Another reason why people fail to keep a safe gap is that overtaking vehicles often slot into the space you have allowed; all you can do is drop back accordingly.

Slip road courtesy

As you approach and pass an entrance slip road, it is necessary to keep an eye on any traffic which may be about to join the motorway. If it is quite safe for you to move from lane 1 to lane 2 without obstructing a driver coming up behind, it is courteous to do so in order to make life easier for drivers joining the motorway; this forethought will be especially appreciated by lorry drivers, who are less able to adjust their speed to blend into the traffic flow. If a junction is very busy, this tactic is particularly appropriate.

Abnormal motorway conditions

Some motorway signs. The top part of this diagram illustrates the gantry which displays the signs, which in this case are showing speed restrictions and an imminent lane closure on a three-lane carriageway. The central part of the drawing shows how the various restrictions are accompanied by flashing lights. The lower part shows other signs that you may come across on the motorway, displaying, left to right: temporary speed limit, lane 3 closed ahead, and the 'clearway' sign, which is not accompanied by flashing lights, to show that the temporary restrictions have finished.

A multiple pile-up on a fogbound motorway occurs almost every winter because so many people drive too fast for the conditions. But there is rather more to it than this. Many drivers make a dangerous assumption when they judge how far they should be behind the vehicle in front: they think that the distance they leave gives them room to react when brake lights appear on any of the vehicles visible in front. What this attitude does not allow for is the very real possibility that the cars in front will come to a stop instantaneously and without warning if they pile into a mass of wrecked vehicles. In fog, you must allow for the stopping distance you need under those conditions.

Motorway fog

Driving in fog on a motorway in other respects is governed by just the same rules which apply to fog driving on any other roads: keep down to a speed which gives safe braking distance within your range of vision; try to keep to lane 1 or 2 (and, in very thick fog, make sure you always know which lane you are in); use dipped beam headlights day or night and fog lamps if you have them (remember that it is just as important to be seen as to see); open the windows, turn on the demister and heated rear window, and use the wipers to keep the windscreen free of moisture.

Above all, be philosophical about the delay to your journey. Rather than risk being a victim in a nose-to-tail crash, it would be better to leave the motorway at the next exit and wait for the fog to clear, even if this means spending a night away from home.

You should not restrict the use of dipped headlights in daylight to foggy conditions. The law requires you to switch on dipped headlights whenever visibility is seriously diminished (defined in the Highway Code as less than 100 metres), so this means in heavy rain as well as fog. You must use your discretion in this matter, remembering that the object is for other road-users to see you, not necessarily to help you to see. Next time you are driving in poor conditions, notice how difficult it is to spot a vehicle without headlights when most have them switched on; headlights attract attention in the rear-view mirror, so drivers ahead will have good warning when you come up behind. Use your car's rear fog lights only when visibility is reduced to around 100 metres, and do not forget to switch them off again when conditions improve.

Motorway warning signals

Automatic motorway signals give you a recommended maximum speed during fog, on the approach to an incident or even during heavy rain, as well as giving warning of lane closures ahead or even the need to stop or leave the motorway in the event of a serious accident. Many motorists do not understand these signals, so it is worth studying the range of warnings shown in the accompanying diagram. Some drivers, furthermore, do not respect these signals, believing that they have been left on by mistake if no obvious need for them can be seen. It is worth confirming, therefore, that the police are extremely diligent in employing these signals when they are necessary and in switching them off as soon as a hazard is cleared. Always obey them, because they serve as warning that you are approaching a hazard, perhaps a mile or two down the carriageway.

These warning signals are so often abused that you may see in your rear-view mirror a car closing quite quickly. Since it is very difficult to judge the speed of a vehicle approaching from behind, it pays to exercise extreme caution and delay any planned lane-change of your own until it is well out of the way. If the signals show that you will need to make a lane-change, perhaps because an accident has blocked one or two lanes, make your manoeuvre in good time and keep below the speed indicated. Keep a careful eye open for the fast-approaching driver in an empty lane who drives dangerously into the slowing traffic stream at the last minute.


Since speeds are normally higher on motorways, you need to be alert to the effect of crosswinds on your car's stability. You may feel this where a motorway crosses open country or a bridge; or you may notice buffeting as a fast-moving coach or lorry passes you. As soon as you feel a crosswind tugging at your car, reduce your speed to a point where you can steer a straight course despite the gust. A light touch on the wheel is important, as too firm a hold will remove the sensitivity of control you need to make small steering corrections.

It is also possible to adapt quite unconsciously to a sustained crosswind by applying a degree or two of lock into the wind to keep your car travelling in a straight line. Be aware of any circumstances where a steady wind may temporarily be shielded from your car, perhaps when passing a heavy lorry or driving through a cutting. You need to be prepared for this by gently correcting the steering as the pressure drops and re-applying your corrective lock when it picks up again. Without this anticipation on your part, your car could swing a few yards across the road - and perhaps alarm other road-users before you manage to correct it.

Leaving the motorway

Taking an exit from a motorway involves a very simple procedure. Generally junction signs are posted 1-mile and 1/2-mile in advance, followed by three-, two- and one-bar signs which provide a countdown starting at 300 yards. It is obvious that you must synchronise your speed with the traffic in lane 1, making sure that you have completed your manoeuvre into this lane well before the three-bar sign appears; in very heavy traffic, you should slot into lane 1 (after checking your mirror and signalling a left turn) even earlier than this, soon after the 1-mile sign if necessary. If you are already travelling in lane 1, signal a left turn in good time, and certainly before you pass the three-bar sign.

Entering the slip road is a potentially hazardous moment. After driving for maybe a couple of hours at close to the legal limit, your judgement of speed will have become distorted. Since 50mph will seem more like 30mph, it is very easy to approach the roundabout too quickly and end up having to brake heavily. Some slip roads curve so sharply that the dangers of misjudging your braking become even greater. Rely on your car's speedometer as well as your judgement when making this big speed adjustment.

While on the subject of judging speed, it is worth pointing out that it is possible to become 'speed happy' while you are still on the motorway. We have already described the tendency for your judgement of braking distance to lapse, but you should also remember that a violent swerve in an emergency could cause you to lose control of your car, simply because you attempt a manoeuvre which you would never normally contemplate at such high speed.

Keeping your car in trim

Once motorways have become a normal part of your driving, guarding against all these hazards should become built in to your approach as you follow the techniques of advanced driving. All that remains is to make sure that your car is able to cope as well as you are. Although you probably keep your car in good trim, a few points are worth noting.

To give their best at prolonged high speed, tyres sometimes need to be pumped up slightly harder than normal. Our speed limits and the frequency with which drivers hop on and off motorways mean that this precaution is more appropriate to driving on the continent, but the higher speeds of motorways do mean that checking the pressure and condition of your tyres becomes even more important. Analyses of motorway accidents have shown that one in six is caused by a tyre failure, so pay good attention to your tyres in order to minimise this chance. A damaged tyre is most likely to puncture or explode at high speed, when the operating temperature rises. If you are unfortunate enough to suffer a puncture on a motorway, brake gently and steer delicately to reduce the chance of the tyre peeling off the rim and rendering your car totally uncontrollable.

Many luxury cars are equipped with cruise control devices, which enable a constant speed to be maintained until overriden by the first touch on the brake or accelerator pedals. In safety terms, there is no reason why a cruise control should not be used, as long as it does not lead you to relax your vigilance; remember that it is all too easy for motorway driving to become almost mesmeric. You should never move your feet away from the pedals when using cruise control, since this delays your reaction to an emergency and may even cause you to hit the wrong pedal in haste.

Motorway breakdowns are often caused by factors which a diligent driver can avoid. Do not push a car beyond its limitations in age and design, and make sure that you have plenty of petrol and oil. Listen for any unfamiliar sounds or vibrations which may signal a mechanical problem. Remember that high speed puts more stress on your car, so the chances of mechanical failure increase on a motorway.

If you are ever forced to stop on a motorway, pull over to the far left of the hard shoulder; use of the hard shoulder, of course, is permissible only in an emergency. Turn on the hazard warning lights and sidelights to warn other road-users, and either stay in the car to wait for a police patrol vehicle or start walking to the nearest emergency telephone. Red arrows on the marker posts (at 100 metre intervals) indicate the direction of the nearest one, which will never be more than half a mile away. Keep well to the left as you walk, and tell your passengers to wait on the hard shoulder, or even the verge; leave any pets in the car. When you are able to resume your journey, do not pull straight on to the main carriageway after moving off; treat the hard shoulder as an acceleration lane, making your move to lane 1 only when your speed matches that of the vehicles around you.


  • When joining a motorway, accelerate up the slip road to a speed which matches that of the traffic in lane 1 and move into this lane when it is safe to do so.
  • Treat the 70mph speed limit as a limit, not as a target which you must reach.
  • Remember the two essential disciplines of motorway driving: maintain a safe braking distance at all times and watch your lane discipline.
  • Treat fog with great respect: drive at a low speed which allows you to stop within the range of your vision, and maintain a braking distance sufficient to give you room if the vehicle ahead stops instantaneously in a crash.
  • Motorway warning signals are always illuminated for a reason: obey them at all times.
  • When planning to leave a motorway, ensure that you have slotted into lane 1 well before the three-bar sign.
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