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Many drivers, not just those learning to drive either, get confused with spiral roundabouts. This tutorial on Spiral Roundabouts aims to help you understand them. Your learning objectives are:
If you can explain how a spiral works, the mystery and confusion of these roundabouts will disappear and you will be able to tackle any spiral roundabout when you come across them.
We have several in Milton Keynes but the one that is really causing confusion is the Denbigh Roundabout down by IKEA/Asda/B&Q in Bletchley. This was laid out as a spiral in June 2013 and since then it is repeatedly used
I have provided a picture of this whole roundabout in pdf form here: Denbigh Roundabout
[NB: if you’re not from Milton Keynes you probably can’t answer all of these questions but if you are planning to do a test in Bletchley you should be familiar with this roundabout and should be able to answer all these questions.]
Look at the RED car. The driver sitting at the give way line waiting to enter the roundabout sees a spiral being created directly in front of them - at A.
The driver of the RED car chooses to enter the spiral at A and follows the RED path.
Using the layout of the whole roundabout can you explain:
You can contact me with your email address and your answers and I will give you some feedback to help you understand spiral roundabouts. You will find a contact form on the home page.
incorrectly and haphazardly by motorists and is a constant nightmare for learners who know they have a high chance of being on this roundabout during their test.
A spiral roundabout is recognised by the short dashed lines that start from the roundabout and work their way out creating a new lane on the inside by pushing the other lanes out. This is possible at each exit because the outside lane on the very left has disappeared.
This layout is popular in multi lane roundabouts because this spiraling out of the lanes makes it possible for you to exit when going right without having to cross multiple lanes on your left.
So, lets’s start at point A. The Blue car on the inside spots the beginning of a spiral (by the short closely spaced dashed line) creating a lane in front of them. In order for this new lane to be created the driver of the Blue car is gently guided to the middle and finds themselves at point B in the centre lane. The Blue car continues round and again sees the start of another spiral beginning at C again creating a lane on the inside and pushing the middle lane to the outside. The Blue car now finds themselves on the very outside lane at point D and they haven’t had to make any lane changes to get there. They have been gently guided out by the creation of lanes on the inside of the roundabout. The Blue car will now exit the roundabout at the next exit as the left lane now leaves the roundabout.
When you enter a spiral you cannot take the next exit you have to continue round to the one after that.
Generally when you are turning right at a spiral roundabout, don’t enter the first spiral you come across. Later spirals will push you out to the left allowing you to exit in the left lane without needing any lane changes. HOWEVER, at the Denbigh Roundabout, approaching from IKEA, if you want to go to Central Bletchley then you need to enter the first spiral you see in order to exit in the middle lane and so approach the two mini roundabouts correctly for Central Bletchley. Also be aware, if you don’t enter the spiral at this roundabout from IKEA direction, you will come into conflict with other motorists on your left who are constantly making a serious error there!!! Maybe you can figure out what they do wrong.