ENGLISH Heritage has called on the Secretary of State for Communities and Local Government Ruth Kelly to seize a once-in-a-generation opportunity' and approve plans for the controversial Stonehenge visitor centre.

It made the plea on Tuesday at the opening of the two-week public inquiry into plans to build the centre on land east of the Countess Road roundabout in Amesbury.

First to give evidence was the chairman of English Heritage, Sir Neil Cossons, who spoke of the importance of Stonehenge and the need for the scheme.

Describing the world heritage site as the "most important, best known and most visited monument in the country", Sir Neil said that English Heritage had developed a proposal that balances conservation and protection of the stones with improving the access and enjoyment that visitors get out of the site.

He said: "The term iconic is overused, but if there is a single site that deserves the term, it's Stonehenge. In 1993 it was called a national disgrace and we have an obligation to do the right thing by Stonehenge to ensure we provide the best possible standards.

"Sites throughout the world will be looking to us, with a wide variety of heritage sites. They will want to see Stonehenge, of all those sites, properly presented."

The proposal for the £67.5m visitor centre, two miles from the monument at Countess East, has been a hugely controversial issue for years with many groups, including residents, conservationists and archaeologists, opposing it. Many are worried about the effect the proposed land train, which will transport people from the visitor centre to the stones, will have on the surrounding area.

The £500m road scheme, which is crucially linked to the visitors' centre proposal, is also an issue of concern.

However, English Heritage claims the development is desperately needed, not only to improve the dire facilities currently provided, but also to prevent the drive-by tourism' of people only experiencing the site through a coach or car window.

Sir Neil said that presently the opportunities to interpret the site are constrained, with no space for exhibitions, displays or educational facilities and English Heritage wants the visitor centre to encourage people to spend more time at the monument and its surrounding landscape, including promoting links with Salisbury and Devizes museums. Sir Neil also used the plans of other sites, such as the Valley of the Kings in Egypt and Newgrange in Northern Ireland, to demonstrate that the work English Heritage has been doing over the last 20 years should be held up as an exemplar.

Stonehenge director Peter Carson gave evidence outlining the scheme and its benefits, which included the positive impact the centre would have on UK tourism and the brand of Salisbury and Stonehenge' in south Wiltshire tourism. Mr Carson said that where adverse environmental effects are unavoidable they have been reduced as far as practicable through design, construction and operational mitigation.

Sir Neil said: "This is a once-in-a-generation opportunity to turn a national disgrace' into a source of national, regional and local pride, and to create an inspiring and lasting contribution to the cultural legacy of the 2012 Olympics."