Further north. My stamping ground now!

Old St. roundabout ?

Not there, SL, further north (but same borough - or perhaps I should say one of the same boroughs as Old St is on a boundary).

top end of holloway road then?

Almost but you need to go north a bit ( I want to know the road it passes under for the point...)

All of archway roundabout is zebra crossings, so is this the Despard rd. subway that goes under Archway rd. about half way to the bridge ? It's a killer to cross that road, good job there's a hospital nearby...

That's the place, Stiffleaf. I thought it would be fairly easy to track down from the last comment.
Actually, there is a subway under the Archway gyratory but it's been boarded up for many years.