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Firstly, I'm sorry if this is the wrong place to ask. I just can't really seem to find an answer anywhere.

My question is, what is the rationale behind hook turns? While I've never performed one, I think I understand how one is performed. I don't have a reason (yet...) to say that they're stupid, but I do want to understand why they're used. According to Wikipedia, it's got to do with trams' right of way, etc. On the Wikipedia page for hook turns, there was also a link to a really interesting newspaper article from 1954. It said that prior to the 1st of September 1954, all of Melbourne's right-hand turns were hook turns!

Anyway, what is the advantage of hook turns? I looked at some diagrams, but I can't really understand how turning right from the right lane would affect trams any more than turning right from the left lane. Are hook turns just used for safety, i.e. easier to see approaching trams?

  • There seems to me to be an implicit assumption that the number of vehicles wanting to make such a turn is small. The capacity per change of the lights is quite low before a queue would back up. This is less of an issue with bikes as they're much more compact. – Chris H Apr 4 '17 at 9:46
  • I very much had to unlearn hook turns when first learning to drive. – gerrit Apr 4 '17 at 18:13
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    it's just because of trams (streetcars). – Fattie Apr 4 '17 at 20:06
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    To make driving on the 'wrong' side even harder for foreigners? – Jon Custer Apr 4 '17 at 20:27
  • But it's still arguably not as bad as a Jug Handle, which is the same type of turn from across the road but requires a much larger paved area. – Moshe Katz Apr 4 '17 at 22:07
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I believe the intent is that cars making a hook turn must wait for the signal to change before crossing, which de-conflicts their movement with the trams. With a normal right turn across tram tracks, drivers would have to do one of two things:

(Note that for the rather mediocre diagrams that follow, I've used an image of streetcar tracks in San Francisco, courtesy Ken Lund, as I wasn't able to find a suitably licensed picture of Melbourne that works for this purpose. Accordingly, the cars drive on the right and the turns in question are left turns. If you're in Melbourne, everything in the Northern Hemisphere is upside-down to you anyway, so this will make perfect sense.)

  • Turn across the tram tracks. This is unsafe and unnatural, as trams going straight may be passing on the right, and it is difficult to check both in front of you (for oncoming traffic) and behind you (for trams). One must be sure it is safe both to cross the tram tracks and proceed across oncoming traffic before turning, and it's just not possible to see all the ways in which you could cause a collision at once. And the consequences of an accident, a tram ramming the side of a vehicle at speed, are fairly severe.

    In the diagram below, the blue car wishes to make a left turn (left turns are actually prohibited at this intersection, though I can confirm this does not stop many drivers from going for it anyway). He stays off the tram tracks and turns across them, following the red line. He is hit on the side by a streetcar proceeding straight through the intersection (green line).

unsafe turn across tram tracks

  • Merge onto the tram tracks and wait for a gap in oncoming traffic. This would greatly delay the trams, defeating the point of (often ignored) dedicated lanes to speed the movements of trams.

    In the diagram below, the blue car wishes to make a left turn. He drives on the tram tracks, enters the intersection, and stops until there is a suitable gap in oncoming traffic (which may take the entire traffic light cycle). An entire tram full of people, represented by the green line, is delayed while a single car waits to turn.

blocking tram tracks

Hook turns provide another solution: get right-turning drivers out of the way of trams and have them wait until the next signal phase before proceeding. This allows trams to continue straight without delay and avoids the risk of right-turning drivers colliding with trams.

hook turn

Here, the blue car moves all the way to the right and gets out of the way. He must wait until the traffic light changes before proceeding; he can only complete the hook turn after the light changes. There is no danger of a collision with the green tram, as it will have a red light before the blue car proceeds with his turn. This video of a Melbourne bus performing a hook turn is also instructive.

According to the paper, "Managing Trams and Traffic at Intersections with Hook Turns"1 (well, the abstract, which is all I've got at the moment anyway), hook turns in Melbourne reduce tram delays, saving a great deal of time and the transit authority millions in costs, while offering "better safety performance than conventional intersections." It also helps that 38% of drivers avoid making hook turns, which is basically the "we'll make something annoying enough that maybe a bunch of you just won't do it" school of traffic engineering. In short, it's about both safety and efficiency.

In other areas with on-street trams and no hook turns, it's not uncommon for turns across the tram tracks (right turns in countries where you drive on the left side, left turns in countries where you drive on the right side) to be prohibited entirely or only allowed during a left turn arrow signal phase, which further slows down traffic as all other vehicles must wait while the left turns take place.


1: Currie, G., & Reynolds, J. (2011, December). Managing Trams and Traffic at Intersections with Hook Turns. Transportation Research Record: Journal of the Transportation Research Board. Transportation Research Board. https://doi.org/10.3141/2219-02

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    Additionally, and especially for e.g. cyclists: you are positioned differently while waiting, and you don't have to look 'backwards' over your shoulder. Better/easier field of view. – Jan Doggen Apr 4 '17 at 7:37
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    The Wikipedia page actually says that the car must wait for the traffic light allowing it across the tram lines. Basically, the hook turn places the car in the cross-street to go straight across the junction rather than waiting in the middle of the road to turn off. – Andrew Leach Apr 4 '17 at 9:31
  • Thank you for the diagrams. Could you say that if you were only allowed to turn on a red light and while in the intersection (therefore trams would be stationary), a hook turn wouldn't be needed? If I understand this answer correctly, it assumes that cars can turn on a green light if the traffic is clear. – Dog Lover Apr 4 '17 at 12:49
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    "And the consequences of an accident, a tram ramming the side of a vehicle at speed, are fairly severe." Not only that, it's a real risk. I've seen it happen with bus lanes twice in 4 years, both times as a bus passenger, both times as the car driver overlooked a bus in their blind corner before the turn. – MSalters Apr 4 '17 at 14:41
  • @DogLover No. Cars cannot turn on a green light if the traffic is clear. They must wait until the green in the direction they are going. – user207421 Apr 4 '17 at 15:02
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You are correct. In Victoria, for reasons that are lost in the mists of time, originally every right turn was a hook turn.

In the mid 1950s this was changed to the 'diamond' turn, and diamonds were painted at vast expense on practically every major and minor suburban intersection to train us. I remember this well.

Diamond Turn

Diagram of a diamond turn

However, originally all intersections where trams cross were exempted from this, and this was later restricted further to just five City intersections: Swanston with Flinders, Collins, and Bourke, and Elizabeth with Collins and Bourke. These were left as hook-turns to facilitate trams. Some time in the late 1990s this was 're'-extended to most of the City intersections involving trams.

The basic idea is to clear the trams before the right-turners. If you're already camped across the tram-tracks waiting to do a right-hand turn, it is not legal for another vehicle, say a tram, to enter the intersection until there is room for it on the other side, which might never happen given that cars can accelerate into that position faster than trams can.

  • Do you mean 'camped on the tram tracks' or 'camped alongside the tram tracks'? Off the top of my head, I'm fairly sure trams in the city have a dedicated lane. Also, interesting about the diamond turn. I'd be interested to see a picture of the painted diamond. – Dog Lover Apr 4 '17 at 12:58
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    I mean what I said. Camped on the tram tracks. It's perfectly possible. You have to cross the tracks some time, lane or no lane. The diamond had curved sides indicating the line to take. You still see them here and there where it isn't obvious. – user207421 Apr 4 '17 at 14:22
  • Interesting. I've never heard it referred to as a "diamond turn", but there are many intersections in the US with short-dashed, curved lane lines helping to define the turning lanes through wide intersections where there are multiple left turn lanes. It helps keep people in the left-most lane from turning into the right-most lane, as they tend to want to do (illegally and unnecessarily, but I digress), and hitting the car(s) also turning left, but in a lane to the right of them. None of these things would be necessary if people paid attention, but again, I digress... – FreeMan Apr 5 '17 at 19:01
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The key point, that isn't exactly obvious in the description, is the vehicles waiting to turn are waiting outside the traffic flow. Meaning, they have essentially pulled over while waiting to turn while forward traffic continues.

They then execute the turn during the signal change after oncoming traffic has stopped.

This is essentially similar to many US States where it is legal and expected to wait to make a left turn inside the intersection. The major physical difference being the turn lane is between the travel lanes.

Very simply, its so the turning vehicle does not block continuing traffic.

  • Note that due to poorly placed lines in Clarendon St South Melbourne they aren't as outside the flow as they should be. The instruction in the driving test manual used to be that you pulled in left to be inside the kerb, and if you were first you advanced right to the kerb in the direction you are about to go. The lines in Clarendon St don't observe this. – user207421 Apr 4 '17 at 14:22
  • At least in Germany, we have no hooks. The rule is for left-turning lanes (we drive on the right side) to wait in the intersection. This solves the problem in a sane way. Straight traffic will just pass on the right. Intersections usually have markings for this purpose so the waiting cars don't go too far and obsctruct oncoming straight traffic. When oncoming traffic gets the red signal, there is enough time for the cars inside the intersection to go left before the lane from right gets the green signal. Probably sounds confusing without a diagram, but seems natural in practice.. – AnoE Apr 4 '17 at 14:47
  • @AnoE Trams going straight can't pass on the right. If you're waiting in the intersection on the tram tracks, you're blocking the tram. – Zach Lipton Apr 4 '17 at 18:02
  • At least in the major city near me, they handled the tram problem by phasing the trams so they interleave with the car signals. I.e., it just so happens that the trams almost never wait, and certainly not in a way that would be fixed with hook turns. I'm not arguing pro/contra here, just giving an alternative point of view. – AnoE Apr 4 '17 at 19:54
  • Actually in many places in the US this isn't legal, and you aren't "expected to wait to make a left turn inside the intersection"; you can actually get ticketed for obstructing the intersection if your light turns red while you're still in the intersection. It's rarely enforced except in smaller towns where traffic fines are a substantial source of municipal income, but I don't want tourists getting nailed for this because they thought it was legal (of course if you're looking for traffic law advice on a SE site you have bigger problems). – Doktor J Apr 5 '17 at 18:21
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This would be better as a comment but I haven't earned comment rights on this SE yet :-) There's a second definition of hook turn which I encountered when learning to drive in New Zealand (and again 30 years later when getting my HT and passenger licenses): On a single carriageway high-speed road (e.g. a rural highway) a hook turn may be used to safely turn across the opposing traffic lane into a side road or vehicle entry. E.g. (driving on the left) - if there is oncoming or following traffic I would pull over to the left shoulder just before the turn point and indicate to the right, waiting until the traffic has passed before completing the turn. This avoids you being stationary in the traffic lane. There are wider shoulders at many rural intersections to allow for this. I have found that in practice, driving a school bus, it sometimes doesn't work - following traffic has come to a halt behind me instead of passing. I blame this on American video games where it is illegal to pass any school bus.

However, on researching, I found that the type of hook turn described in the wikipedia article linked above has recently been introduced in New Zealand.

  • Correct - in NZ you're supposed to pull off the road and wait till its clear in both directions, instead of stopping in the traffic lane. Its been this way forever but many drivers don't know or forgot. Also, in NZ many of the high speed roads are one-lane each way, with only a painted line as a separator.. There's not a lot of room when things go wrong and nothing much to prevent head-on accidents if someone "crosses the centerline" – Criggie Apr 5 '17 at 8:05
  • Some roads in France are built with lanes/bays to facilitate this, and signed accordingly. It tends to be where an entrance to somewhere expecting slow turning vehicles is on a fast road, such as a factory or campsite (caravans) where the speed limit is 90km/h. – Chris H Apr 5 '17 at 9:16
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    It's not just "video games"... In the US, it is illegal to pass a school bus from any direction if the lights are flashing. If the bus is just waiting to turn (with a turn signal on, one would hope), passing on the non-turning side is perfectly legal (assuming there is room to do so). – FreeMan Apr 5 '17 at 19:05
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The reason is 'trams'. Right turn movements requiring dedicated phases/filter turns tend to delay tram throughput. By having hook turns, intersection can simply be managed in two simple phases increasing efficient for trams.

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