How history and memory inscribe themselves upon land, and the way the physical characteristics of a city impact upon the life of its inhabitants, have long been core concerns for Clive van den Berg, and were once more a theme in his contribution to the 'Fault Lines' exhibition at the Cape Town Castle in June 1996. A military base, the Castle became the site in which Van den Berg also addressed the matter of love between men. On a steep escarpment of grass, graded from ceiling to floor across a room and subject to decay, Van den Berg presented the bodies of two male lovers. Only the heads were visible. A bed was burnt into the grass, a black halo encompassing the lovers. Stranded on the green slope were white paper constructions of a ship and a gaping suitcase, spilling rocks. Under the tide Men Loving, notes read: 'In 1735, two men were taken into the Bay off Cape Town when the ship was near Robben Island. They were made to "walk the plank" while chained together. They had loved each other.' A gap follows, and then: 'On Friday May 8 we adopted a constitution which forbids discrimination on the basis of sexual preference. Perhaps now loving will be easier.'

For the 1995 Johannesburg Blennale, Van den Berg had also elected to burn his iconic images onto landscape. While William Kentridge and Doris Bloom decided on Newtown, the epicentre of the Biennale, in which to create their fire drawing of a 'utopian heart' gate, Van den Berg chose mine dumps, one next to the freeway linking the city and the airport, and the other flanking the Soweto highway. While the frill effect of Kentridge and Bloom's fire drawing demanded a photographic record from the sky, the mine dumps had the immediate and simple advantage of existing elevation.

'The loveliest thing would be seeing people stop,' says Van den Berg. 'At some stages there'd be great lines of cars. People would communicate with me or whoever was up there was by flashing their lights. A lot of people didn't know who had made the drawings. The interaction was spontaneous.' The potency of Van den Berg's fire drawings remains indisputable. His giant head, armchair, double bed and staircase, shaped and illuminated by braziers, caught the imagination of what Van den Berg terms 'a chance audience'.

Van den Berg's objective, however, was not only to create a 'public art', but also to draw attention to those most contentious and problematic sites: the mine dumps. For Van den Berg, these remain one of the most charged signs of the 'avarice' of Johannesburg. 'They are manifestations of history, although unrecognised as such,' the artist says of his choice of location. 'It's incredible how naturalised they've become. People see them as geography rather than as manmade things which have been piled up as the result of labour. I wanted to make people look at them again and to recognise that they were our past. It really troubled me that they were disappearing, that the mining companies were reprocessing them. I may he cynical ... reading other reasons into their disappearance ... such as making the environment an innocuous ahistorical place ... it disturbed me that we were going to be left with a city which had no markers to why it had started.'

The fire drawings remain visible today. To ensure maximum and lasting visibility, the grass was embossed and cut with a weed-eater so that 'even a year later, because the grass grows at different rates, you can see the memory of the images'. If fire is incandescent and transient, it remains as 'a way of branding, as an act of burning into memory'.

Van den Berg's concern with the erasure of memory and the conflation of geography and man-made structures is an urgent one. For Van den Berg, the job of art is to remember, to activate the silenced workings of history.

Sue Williamson and Ashraf Jamal in Art in South Africa - the future present