Remember my walk across London last year? I want to do something similar just before my birthday this year [the 28th of April].

Last year, I walked east to west, from Canning Town to Chiswick. This year, perhaps, I should go north to south. I haven't decided on a route yet.

My first thought was that it might be quite fun to follow an Underground line, above ground. I could follow the Northern Line, from Edgware to Morden, passing through Hampstead, Camden, the west end, down to Kennington, Clapham, Wimbledon. That doesn't exactly fill me with enthusiasm, though, as I know these areas well, and the last part is deathly dull [apologies to the residents of Tooting].

The Victoria Line may be more intriguing - Walthamstow, Tottenham, King's Cross, Vauxhall, Brixton. This passes through areas of vastly different ethnicities - Asian, orthodox Jewish, Caribbean - and socio-economic scales. Again, though, I am too familiar with the latter half of the route.

I suppose I need to avoid central London, taking a route north to south in east London, or west. Or west to east across the top or bottom of London.

Can you suggest a route, of about fifteen miles, which:
(a) takes me from one end of London to the other
(b) avoids central London
(c) goes through some groovy, or dilapidated, or historical areas