On my way into Salisbury I encountered a traffic queue on the A30, it was stop start for about a mile but it did keep moving. Then I saw the problem, three cars had shunted one another and an ambulance was there in attendance. One side of the road was blocked but drivers were behaving very reasonably and letting the ‘other side’ have a go when needed with the result that both sides were moving at a reasonable pace considering the circumstances. Once passed the accident it was onwards to Salisbury bus station and an immediate turn round because I was now about 10 minutes late. However, as I approached the accident again it was obvious that the traffic was far worse with nothing moving for ages. When I finally got to the accident the ambulance had gone (it had been on the same side of the road as the accident) I found a police car on the previously clear side of the road and a policeman ‘controlling’ the traffic through the chicane he’d created with his car! Utter chaos where 30 minutes earlier all had been polite and orderly.