By "best" Nairn meant also the worst (the ugliest house in London, the most stygian Underground passage), and what he looked for was the real thing: "I have all the time tried to be rigorous--not any old Wren church or view or pub, but the good ones--and I have all the time tried to get behind conventional aesthetics to an internal reality in which beauty is only one facet. What I am after is character, or personality, or essence."

During the next several years I worked my way through Nairn. I will not say that I have completed his Chapter 11 yet (West London: Kensal Green to London Airport), nor have I been to Epsom or Barnet, but I have been many times to Sir John Soane's breakfast room ("If man does not blow himself up, he might in the end act at all times and on all levels with the complete understanding of this room"). And I have visited Soane's Bethnal Green Church, and his stables in Chelsea, and his Dulwich Art Gallery, and read books about him--for that is the way Nairn works, leading you by specific examples into a general curiosity.

I remember the day I wandered the side streets beyond Lord's Cricket Ground (not listed, although Lord's Tavern is) until I stood before 77 Langford Place ("Sheer horror: A Francis Bacon shriek in the affluent, uncomplicated surroundings at the end of Abbey Road") and admired its bay window "like the carapace of a science-fiction insect." And the many days I walked along the Thames; in the earlier years on the South Bank you could still smell the spices from the Orient, permeating the bricks of the old warehouses which later became condos, or were replaced by the modernist concrete bunkers Nairn despised. And I remember days along Fleet Street and the byways of the City, and beyond Notting Hill to Lord Leighton's House.

Walking around London has been a pastime of mine since 1965, when I passed through in January on my way home from Cape Town, and found that the writer Daniel Curley, my professor at Illinois, was on sabbatical there. He was a walker. He led me across Hampstead Heath to the Spaniard's Inn, Kenwood House and Marx's grave, on a journey that led to our book "The Perfect London Walk." We also walked along the canal towpaths into Regent's Park, and saluted Dick Whittington's cat.

Now, with Nairn, my scope expanded. Following the book was like having an opinionated, passionate and eccentric guide, who remembered a great London and treasured what was left after the destruction of war and "renewal." "It was Nairn's pen more than any other," wrote Deyan Sudjic in an obituary appreciation in the Sunday Times, "which helped unleash the deluge of protest that erupted in this country at the damage being done by crude and incompetent new development."