The A5227 is an extremely unusual A-road - primary, single carriageway, less than half a mile in length and elevated for almost its entire duration!
It lifts off from the central reservation of the A41 close to Birkenhead town centre, permitting access to and from the south. The two directions of traffic begin as separate ramps but join as they rise and turn to face west, forming one elevated single-carriageway road.
The road then runs in a straight line past the marshalling areas at the Queensway Tunnel entrance, immediately adjacent to another one-way flyover carrying vehicles that have exited the tunnel.
After a journey that is measured in seconds, our flyover drops to ground level (the other one remains elevated) and the road terminates abruptly on the roundabout at Clifton Crescent on the A552.
An amended OpenStreetMap trace for this route awaits uploading to the SABRE Wiki.