Well done, Sherlock, it's in N19 between Holloway Rd and Hornsey Rd. How know you this? What's the story - a youthful five stretch in Pentonville with day release privileges to Archway environs? Inquiring minds wanna know.
Ha!
At one time I lived close to Belsize Park and remember walking by a similar door. It wasn't this particular door, but now every time I see one like it I just assume it's North London.
London properties/profit margins are getting narrower and narrower.