The 3.x mile section of dual carriageway from Cheltenham to Gloucester, known as the Golden Valley Bypass, crossing junction 11 of the M5 was at one stage a no-cycles route (after modifications to road level to clear a bridge.
When it was made a no-cycle route the pushbikers were up in arms about it. Days after the restriction was lifted a cyclist was in collision with a motor vehicle, can't remember whether they survived or not. The old road is safer, to an extent.