Quiz: How well do you know the M4?

If you live or work in Wales, you're bound to have travelled on the M4 at some point. The busy route is Wales' only motorway, and it's used by tens of thousands of people each day.

It's often the subject of criticism, both for the lengthy queues that build during rush hour and after a traffic accident and, most recently, due to a government proposal to charge people to use it.

But how well do you really know the route? Do you know what makes it unique? Test your knowledge in our quiz and let us know how you did in the comments. To open the quiz in a new window, click here.

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