Said a spokesman for SCSO: "Sadly, Worthing councillors have forgotten the public purposes for which this downland was acquired. It is our job to remind them - this land was acquired by the council many years ago to protect it, for the benefit of Worthing people.

"The council played a central role in helping the National Trust buy Cissbury Ring itself – the Iron Age Hill Fort and its Stone Age flint mines and ancient wildlife. The council also donated part of Highdown Hill to the National Trust. Now they just see their own downland as a ‘piggy bank’ to raise a bit of money.

"They are asking a mere £200,000 for the Mount Carvey land, the real value of which is priceless. This land is to Worthing what council-owned Beachy Head is to Eastbourne, or Stanmer Park is to Brighton. It is our green lung."

The council-owned land at Cissbury is in two bits. One bit comprises a mile and a half along the ridge of Tenant Hill between Charmandean and Cissbury Ring. The other bit comprises three quarters of a mile of downland on Mount Carvey, between Findon Valley and Cissbury Ring.

The campaigners point out that there is lots of money available to Worthing to help them enhance this land.

Said the spokesman: "A special scheme to help farmers care for the environment is now available to local councils. It is called Higher Level Stewardship (HLF). The new National Park will help Worthing with their expertise. The National Trust will be interested in working in partnership for this enhancement, which will also benefit their property at Cissbury Ring. There are budgets available for enhancing public recreation and conserving special wildlife."

Added Ms Ashbrook: "The Open Spaces Society has campaigned to save our open spaces for more than 140 years and is pleased to add its weight to this crucial campaign for the Cissbury downland. This is of exceptional value for its landscape, chalkland habitat and public enjoyment.

"It forms a vital part of the setting of the celebrated Cissbury Ring, and is within the new South Downs National Park.

"We have written to the leader of Worthing Borough Council, Paul Yallop, calling on him to withdraw the sale of the land. Worthing acquired the land to protect it for the benefit of Worthing people. It must not only keep it, but also maintain it for its exceptional qualities and for public appreciation and enjoyment.

"On the edge of the south coast conurbations, it is especially important to those communities, who look up out of the towns to the fine, ancient landscape of Cissbury Ring. It is their pleasure ground, and it is right that Worthing should own it for those people and for the nation.

"Worthing must restore and enhance this landscape — it would be a great and, literally, high-profile project for it to engage in."

SCSO is urging people to write letter to councillor Paul Yallop, the Worthing council leader, asking him to withdraw all the downland from sale, and accept the help which is available to enhance the downland for the benefit of all. These should go to to Cllr Paul Yallop, Town Hall, Chapel Road Worthing or e-mail: paul.yallop@worthing.gov.uk. Supporters are also asked to write to the local papers, and to their ward councillor.

Stop Cissbury Sell-Off website: www.scso.co.uk