Road signs, markings and traffic controlQuestion #16332
What does this road marking indicate?
Explanation
The area marked with yellow lines where carriageways meet (the "yellow box") shows a spot you must not enter if there is an obstacle in it or beyond it — such as a traffic jam — that would force you to stop in the junction and block traffic from other directions.
KET reference: KET appendix 3, 1.32: an area marked with yellow lines where carriageways meet shows a spot you must not enter if there is an obstacle.