A public inquiry into whether ramblers should be allowed on to Madonna's £9m estate opened on Wednesday.
Madonna launches 'keep off my land' appeal
A new right-to-roam law would allow walkers access to parts of the pop star's 1,200-acre retreat, Ashcombe, near Tollard Royal, Wiltshire.
Madonna and her husband Guy Ritchie are concerned that photographers and sightseers could legally get within 100 yards of their Georgian mansion.
The singer and her film director husband did not attend the inquiry.
Mr and Mrs G Ritchie - as the showbiz couple are listed in legal papers relating to the case - have appealed against the agency's decision to mark about 100 acres of their land as open countryside.
The couple believe the decision would breach their human rights by creating an infringement of their privacy by allowing public access to their land.
They also argue that the description of their land as open countryside is inappropriate and does not reflect the general environment and layout of the property and surrounding area.
The hearing, headed by the Planning Inspectorate, is expected to take up to five days.
David Elvin QC, representing Madonna and her husband, told the inquiry that 12 pieces of land were still subject to dispute and his
clients believed they had been wrongly labelled by the agency.
Mr Elvin said that the appeal by the Ritchies was only the third by landowners to be heard against the provisional map of all land in England created by the Agency.
The parties at the inquiry, including representatives from the Countryside Agency and the Ramblers' Association, were expected to take a two-hour tour of the disputed land on the estate on Wednesday afternoon.
The eight-bedroomed property was the former home of society photographer Cecil Beaton.