You are driving along a one-way street when you see a triangular warning sign with a red border showing one black arrow pointing straight up and another pointing straight down. What is this sign telling you about the road ahead?
- The one-way street continues indefinitely, and the arrows simply confirm the direction of permitted travel is unchanged
- The one-way street is about to end, and you will shortly join a two-way road, so you should keep to the left and be ready for vehicles coming from the opposite direction
- The road ahead splits into two separate one-way streets running in opposite directions, and you must choose one before the split
- The road ahead is subject to contraflow bus and cycle traffic only, while other vehicles continue to travel one-way as before
Why B? And why not the others?
Correct answer: B. The one-way street is about to end, and you will shortly join a two-way road, so you should keep to the left and be ready for vehicles coming from the opposite direction
A red-bordered warning triangle showing one arrow pointing up and one pointing down is the 'two-way traffic crosses one-way road' sign in its vertical-arrow form, used where a one-way system is coming to an end and the road a driver is on is about to carry traffic in both directions again. Because it is a warning sign rather than a direction sign, it does not itself instruct a turn; it simply alerts the driver that after this point vehicles may be approaching from the opposite direction on the same carriageway, so the correct response is to move over and keep to the left in readiness, not to assume the one-way restriction simply continues. The same sign design also exists with horizontal arrows, which instead warns of a junction where a driver must turn left or right to join a two-way road, so the vertical-arrow version specifically signals continuing straight ahead onto a two-way section rather than a mandatory split or a contraflow lane reserved for buses and cycles, which each have entirely different signs of their own.
Source: DfT Traffic Signs Manual — Two-way traffic crosses one-way road (GOV.UK)