Birmingham single track

Sunday was spent investigating National cycle route 5 into the city centre, and then out towards Ladywood, round Edgbaston reservoir, and then down the Harborne walking route (a disused railway line).
I found that the old line was probably as close to a "single track" as you could find in Birmingham. OK, you aren't hurtling down hill, but some technical riding is required with small logs/branches/roots to be negotiated.
The Rea route[1] into the city is a very pleasurable ride. I need to time the difference between using the Pershore Rd to the Council House, vs using the cycle route, using the same bike.

[1] The rangers are also funded partially out of Selly Oak NRF, and the route extends as far as the entrance to Cannon Hill park, not just to dogpool lane.