Map-maker's aids become pillars of the community: An adoption scheme for redundant 'trig' stations is proving a success. Oliver Gillie reports

THOUSANDS of people all over Britain are volunteering to adopt abandoned 'trig pillars', those familiar concrete monuments used by the Ordnance Survey to map the country.

With the advance of satellite mapping the Ordnance Survey has decided to retire 5,000 of its 6,000 trig pillars because they are no longer needed to pinpoint accurately the positions of landmarks. The Ordnance Survey has decided to stop inspecting and maintaining these pillars and is looking for people who will volunteer to do it for them.

Andrea Wilkie is hoping to adopt her local trig pillar at Cobley Hill, near Alvechurch, just south of Birmingham. Last week, with encouragement from the Ordnance Survey and permission from the local farmer, Mrs Wilkie painted her pillar white.

'I think we will have picnics here with the children in the summer,' Mrs Wilkie said. 'It is my triangulation station.'

The words 'triangulation station' are moulded in brass at the top of the pillar where there are three anchor marks for a theodolite, the instrument used to take bearings on distant points. 'I am wanting to find a secondhand theodolite,' Mrs Wilkie said. 'Then I shall be able to set it up at Cobley Hill and look at my friend Helen, who is hoping to adopt her local pillar at Worcester Beacon.'

Mrs Wilkie's station, BMS5503, is at a height of 618 feet (188 metres) and commands views of the Cotswolds, the Malverns, and Bredon Hill to the south. The pillar itself is hollow with access via a brass fitting at the top secured by small nuts. One person has used the cavity of a pillar on Helvellyn in the Lake District to inter the ashes of his late mother.

About 2,000 of the 5,000 redundant pillars have already been assigned on a first come, first served basis. The person adopting must inspect the pillar twice yearly and paint it when necessary.

Wendy Fellingham, in charge of the Ordnance Survey's adoption project, said: 'Some people think of the pillar as a new family member. One woman in Devon told me that she and her husband were able to take on a pillar now that their children are at college.

'One man has written poetry to his pillar and called it trig point Charlie after his grandfather. But some people have started to worry about what sort of relationship they will have with their pillar - one woman became very anxious and asked me if I thought her pillar would reject her.'

All the trig pillars in the Lake District, the North Yorkshire moors, the Dales, Brecon Beacons, Dartmoor, Exmoor, the Malverns and the Sussex Downs have already got prospective sponsors. But pillars are still readily available in the Midlands and other more populated areas.

'Some pillars are in hedgerows. One is in the middle of a dual carriageway going into Leeds. Those sort of pillars don't excite a lot of interest,' Ms Fellingham said.

One pillar, Top Tax, near Kidderminster in Hereford and Worcester, may have been rejected because of its name. Another lonely pillar is on the top of Deadwater fell in Northumberland. It is next to an RAF radar station and seems to have been used by soldiers who have made an improvised hideout next to it.

'It could do with care and attention from a demanding sergeant major or perhaps an officer's wife,' Ms Fellingham said.

(Photographs omitted)