Re. the milestones:
I grew up just off Soho Road, and regularly passed the milestone near to Milestone Lane - logical that the lane was so named because the milestone was there? Presumably, this is the stone reported to be at Holyhead School.
I also passed the milestone outside Dennison's at the top of Soho Hill, when on the bus into town. The last time I remember both of them was, I think, around 1970.
The concept of milestones is that there was one placed every mile along a route (hence one shows 111 miles, and the other, 110 miles), so not only were there the two mentioned in this thread, but there must have been others!! Working towards the city from the top of Soho Hill, a mile away is Great Hampton Street -does anyone remember if there was a stone along there?
Similarly, there should have been one near the Birmingham/West Bromwich boundary.