What should you do?
Plan your route early, stay out of the left-turn position and continue straight or follow another permitted direction.
How to recognise it
A red-ringed circle with a black arrow bending to the left, crossed by a red diagonal bar.
Common confusion
Do not mix it up with the blue circular 'Turn left' sign, which orders you to turn left rather than forbidding it.
Explanation written by the My Driving Test editorial team using the Department of Transport Traffic Signs Manual conventions and the RSA Rules of the Road.
