"Right," said Sinclair, straightening up. "Are you ready for the zone? From here on in it's pure Tarkovsky." And so it was. Light-industrial spaces, car-wrecker's yards, square-windowed studios, haulage depots. Then, a mile further on, we hit the fence.

The perimeter of the Olympic site is now secured by a plywood fence that is 10ft high, around four miles long, bright blue in colour and chinkless. In places it is double-banked, in others it is topped by razor- or barbed-wire. The ODA began its construction last spring, and the last sections were put into place in July.

The fence is a barrier designed to exclude not only access, but also vision. There are no viewing windows built into it, no portholes for the curious stakeholder. To see inside the zone, you must ascend a Stratford towerblock, hire a helicopter, or - the desideratum - visit the ODA's website, which provides stills of the construction process and mocked-up futuramas of the park (light-glinted buildings, sparkling water features, happy munchkin people).

From our first encounter with the fence, we walked widdershins: south past the Big Breakfast House, east over Stratford marsh, north up through Stratford New Town, before returning west across Hackney Marshes. Sinclair told me about the work of the photographer Stephen Gill [1], a friend and fellow Hackney resident. Three years ago, Gill bought a camera for 50p in Hackney Wick market. He began using it to document the lives and spaces of his borough: its birds, flowers, roadworks, signs, cashpoints and people. One result of this was Hackney Wick, a photostudy of the area. The book was published in a small print run and became a cult success. Copies change hands for several hundred pounds. Jon Ronson and Geoff Dyer are now among Gill's on-record admirers.

Gill's new book is Archaeology in Reverse [2], and its 100 uncaptioned images were taken on the same cheap camera. For about a year - between the beginning of work and the completion of the fence - Gill haunted the Lower Lea on bike and on foot, watching as the first stages of the Olympic vision were rolled out. The result is a remarkable book that, in Gill's phrase, records the "traces and clues of things to come". His subject is the imminence of mass construction, rather than its realisation.

From: London Fields, Robert Macfarlane, The Guardian, December 8, 2007

See more at: Macfarlane [3]