Ann Gloag, the Stagecoach tycoon, yesterday won a landmark legal ruling banning ramblers from entering a large section of her Perthshire estate.

Following a judgment at Perth Sheriff Court yesterday Mrs Gloag, who is worth an estimated £400m, became the first individual in Scotland to exempt her land - around Kinfauns Castle, near Perth - from the right-to-roam legislation.

The Land Reform Act, which enshrines the right-to-roam law, was one of the first flagship policies of the first term of the newly created Scottish Parliament.

In a 34-page judgment Sheriff Michael Fletcher said the "nature of the building and its prominence" meant a larger section of surrounding land was required by Mrs Gloag to ensure her privacy and enjoyment of the house.

Mrs Gloag, 64, a former nurse who made her fortune with the success of the Stagecoach Group bus empire, last night welcomed the ruling.

A spokesman for Mrs Gloag said: "We are delighted that the sheriff has recognised the importance of the right for everyone in Scotland to enjoy reasonable privacy within their own homes.

"There has been a misconception that this legislation only affects people with large homes and gardens but this is not the case. This legislation has affected people all over Scotland.

"We have always tried to accommodate responsible ramblers. The area which has been recognised as private' is only part of the land surrounding Kinfauns and the remainder continues to be accessible to all."

The spokesman added: "Mrs Gloag plans to spend many happy hours in her garden with her family and grandchildren and hope those responsible people who love the countryside continue to enjoy walking on the other parts of her estate."

However, politicians and campaigners called for a review of the legislation following the decision.

Dave Morris, director of the Ramblers Association Scotland, led a chorus of disapproval, expressing disappointment at the ruling, which he said did not appear to reflect properly the intentions of the parliament when it passed the act.

He said the organisation would seek legal advice on whether to appeal against the decision.

Pauline McNeil, Labour MSP, who was convener of the Justice 2 Committee which was responsible for dealing with the Land Reform Act, said: "This decision is wrong and is not in the spirit in which the Scottish Parliament intended the act to be inter- preted."

Former Labour MP Brian Wilson, who as Scottish Office Minister in 1997 helped instigate the land reform package, said: "This ruling suggests the legislation which went through Holyrood was not tight enough in achieving its clear objective on access."

Cameron McNeish, editor of TGO, Britain's leading magazine for walkers, said: "This makes a mockery of the access provisions of the Land Reform Act. For Ann Gloag to suggest barricading herself inside an electrified fence will keep her safe from abduction is a complete nonsense."

Perth and Kinross Council said it was disappointed at the decision and is considering the implications of the judgment in more detail.

A spokeswoman for the Scottish Executive said: "We will consider in detail the judgment and consider its impact on current legislation."

The court proceedings centred on a 7ft high perimeter fence which was erected around part of Ann Gloag's estate without planning permission. Retrospective permission was later granted by the council, but the local authority and the Ramblers Association wanted a stretch of the one-mile fence moved.

When the council and ramblers appealed to have a section of the fence taken down under right-to-roam legislation, Mrs Gloag lodged an application at Perth Sheriff Court in an attempt to protect her privacy, citing a fear of being kidnapped, and the fact she stores valuable artefacts and jewellery in the house.

In October Sheriff Fletcher visited the castle which Mrs Gloag bought for £4m in 2005 and which is set within the 28-acre estate off the main Perth to Dundee road. He ruled yesterday that the fenced area in question, about 12 acres, was not land which could be accessed under the terms of the the Land Reform (Scotland) Act. Instead it falls under section 6 of the act - land which is exempt from the act for reasons of privacy or enjoyment by the owner.

Keith Arbuthnott, chairman of the Scottish Rural Property and Business Association (the former Scottish Landowners' Federation), said: "We don't know the detail of the judgment yet. But it is reassuring to some of our members that they can obtain some privacy and security."

Jim McLaren, president of the National Farmers' Union in Scotland, said: "The majority of farmers support legitimate, responsible access to countryside as long as it does not interfere with the practice of farming.

"I wouldn't be anticipating a flood of challenges to the right-to-roam legislation in light of this judgment."