'LOOK," says Iain Sinclair, showing me sepia photographs of two fine upstanding men: "My great grandfathers - from Aberdeen!" As a writer, Sinclair is so thoroughly thirled to London that the excitement, or relief, one or the other, is palpable when he gets the rare chance to talk about someplace else.
Scottish on his dad's side, he's only ever made one trip north. "It was for a funeral in mid-winter and before the oil money so Aberdeen was pretty unforgiving. But the great thing for me was happening across a pile of Broons and Oor Wullie annuals. I remember lots of jokes about meanness: flag days in Aberdeen, with no one on the streets. I must try and get back there sometime."
Sinclair, 62, is so masterful at observing London, and especially the bits that normally go unobserved, that on the journey to meet him I find myself acting as a kind of "local colour" researcher, collecting unsolicited vignettes of street-life for him, even though I know they will fall short of his standard.
What, for instance, would he make of the Euro Cafe, close to his Hackney home, full of workies, one in a Celtic football top ... or this advertisement on the Underground: "Everybody here could well be one - you just don't know it"? (This is a puff for an online poker service, not a warning to watch your back... your backpack.)
He walks, then writes, sometimes fiction, like the last book, Dining On Stones, other times he's our guide, as in the new one, Edge Of The Orison, and even the briefest directions to the house are lyrical: "There's a ghost of a bridge - turn right." Sinclair finds a strange beauty in just about everything, even motorways, even the M25 - his best-known work, London Orbital, the one which confirmed him as a great British eccentric, was a tramp round its 120 miles, "a journey that no sane Londoner could be accused of attempting".
He writes so well that I had been expecting him to be formidable, intimidating. Instead, while his wife Anna serves tea, he chats cheerily about city living: bad politicians and bad planners, crime and grime, gentrification and alienation, sandblast and bombast. Still, I say, he must be looking forward to the Olympics coming to London in 2012.
"As a Londoner, I dread them, but for a writer it's going to be a deeply interesting time," he says. (Something tells me he doesn't really mean "interesting".) "I think quite a lot of what's going to happen will be grotesque. I expect a huge surge of scams of every kind. Two weeks of hype got us the Games, now we're in for seven years' worth of pulling down old buildings, makeovers, etc.
"There's always this contest between the virtual and the actual. Reality is airbrushed and we're given promises of fabulous, mythical oases of futurity. The plans for the Millennium Dome made it look beautiful: the Thames was brilliant blue; there were orchards. They should never have built it; they should have given us headsets so we could experience it in our homes.
"So the Dome, Wembley Stadium, Pickets Lock [site of the failed athletics stadium, a carcinogenic hellhole, resulting in London being stripped of this year's World Championships], the Thames Gateway [Europe's largest regeneration project, monumental in its blandness]... What on earth makes London think it can stage these Games?"
He thinks back to July when the Olympic bid was won: "a night of hubristic celebration, we were all required to rejoice", then 24 hours later, the terrorist bombings. "I think that double-header is like an awful dark cloud hovering over the next seven years: ever more grandiose schemes, ever more dangerous undercurrents of people who have been marginalised and excluded and have no voice and will erupt through acts of astonishing terror."
How did the metropolis react to the outrages? "Rather than melancholy and fear, there was a great surge of spirit and energy and debate was initiated about what it's like living in London and how you move around the city. But the moment passed and now it's almost ancient history, although for many the bombings finally stopped them using the Underground because it's a system that just isn't working." So what's the solution for the Tube? "I would close it, or only use it for moving goods around."
For Edge Of The Orison, Sinclair thought he was leaving the urban behind. He headed for Essex to retrace the escape, in 1841, of the "peasant poet" John Clare from High Beach Asylum in Epping Forest, and his three-and-a-half day walk in search of his lost love, a woman already three years dead.
But it wasn't long before a modern madness presented itself: John Prescott's vision of Britain. On a "Ballardian landscape of secret airfields and abandoned industrial farms", Sinclair viewed with horror the spread of Barratt-style living: new towns swallowing up old villages; more generic, satellite hotels for breakfast meetings, more Tesco Metros, and orbital motorways which you circle forever.
"I thought this was a metropolitan thing, but it's happened to Peterborough and now there's to be a Cambridge Zone. The villages of Clare have been swallowed into the city sprawl. The people I met on the journey were kind of dazed and lost. The battle is between established ancient settlement and this tidal wave of anonymity. It's a nightmare."
Sinclair gets many requests to guide his own literary tours: he cannot think of anything worse. This kind of recreation is "over-organised: signs saying 'You must walk here' and laminated boards with pictures of herons. My books are about achieving your own memories and respecting other people's".
A couple of years ago, he seriously contemplated leaving London for the south coast and Hastings. But in the end he couldn't do it and now reckons they're stuck with each other: the metropolis, getting ever more grungy and dangerous, and its chronicler, whose Hackney home was condemned when he moved to the district 36 years ago and has outlasted the tower blocks built after it. But while High Court judges now live in an area once inhabited by Charlie Kray, three murders have recently occurred within 100 yards of his front door.
Where are the visionaries who can change things? Ken Livingstone offered hope, he says, because he wasn't New Labour, "but now he's built City Hall, which isn't in the City and isn't a hall, but is all about allusion to New York. There are people of vision but unfortunately they're not working in politics: think of Christopher Brooker [producer of the classic BBC documentary on the multi-storey-dream-gone-wrong, City Of Towers], think of Mike Davis [author of City Of Quartz]..."
And think Iain Sinclair.
Edge Of The Orison (16.99, Hamish Hamilton) is published on Thursday