Ghosts in the pavement

As protesters gear themselves up for the Government's next round of motorway-building, those who are interested - but not committed enough to take up residence in a tree - might turn instead to Linked.

This intimate, impressionistic piece encourages the audience to walk between Hackney Marshes and Redbridge, wearing headphones and an electronic device that lets them pick up voices describing the area's past.

More than 400 houses were

destroyed so that the M11 Link Road could be built, and the artist Graeme Miller has created a soundscape that evokes the minutiae of personal lives pushed aside in the name of progress.

Carefully positioned radio transmitters mean that the audience are aware first of whispers and mutterings, until they come to a point where there is a clear narrative, either giving personal details - "my father was so strong he could lift an ox" - or describing the wider social impact of the moment when residents discovered that the Link Road was going to destroy their way of life.

Miller's creation is part of an interesting emerging trend where electronic devices - such as radio transmitters, or global positioning systems - extend the idea of a site-specific work so that a whole new landscape is covered.

When Linked works, it creates a powerful sense of ghosts seeping up through the paving stones - but it also has its frustrations: if a car goes past, or somebody talking too loudly on their mobile phone comes close, it is impossible to tell whether someone is talking about a murder or recounting fondly the days when smogs descended on a regular basis.

Despite the imperfections, it is easy to sense the seductive potential for unlocking London's multi-layered past. Politically it might also make an interesting afternoon for Transport Secretary Alistair Darling.

Until 20 August. Information line: 0800 389 1035.