A major inquiry into the future of the South Downs began today.

After years of public consultations, protests and plans, lengthy negotiations on whether the hilly fields and woods stretching through Sussex should be designated as a national park have started in Worthing.

The hearing, expected to continue for at least seven months, follows heated debates on what land should be included in the proposed national park boundary.

National park status grants a high level of protection from development. As the South Downs is gradually chipped away by builders, many feel such protection is crucial to their survival.

Government adviser the Countryside Agency was today due to tell the inquiry that national park status was imperative to protect the Downs.

Jane Cecil, the Countryside Agency's Head of Finest Countryside, said: "It would fulfil Sir Arthur Hobhouse's original vision for national parks set out in 1947.

She added: "This area of quintessentially English lowland landscape stretching for more than 116km from Winchester to Eastbourne should be a national park because it is worthy of that status and needs the integrated management that national park designation would bring.

"Designation would provide the resources and strategic vision that the South Downs needs for the special qualities of the area to be conserved.

"A National Park Authority will work to increase awareness of the special qualities of the South Downs and the fragility of its important habitats and landscape character."

David Thompson, Senior Countryside Advisor, also appearing for the agency, said: "As well as being outstandingly beautiful and rich in wildlife and history, the Downs are an exceptional recreational resource of national importance accessible, including by public transport, to a large urban population."

The public inquiry, which is sitting at the Chatsworth Hotel, Worthing, is expected to last until September 2004.