Covert castle builder Robert Fidler has vowed to "fight all the way to the top" to save his home from demolition.

The farmer made the defiant claim this week after appearing at the High Court in London to appeal a Government decision to tear down his "dream home".

Mr Fidler, 60, took two years to build his secret citadel behind a barricade of 40ft straw bales on Green Belt land at his farm.

He put Salfords firmly on the map after revealing his castle to the world – and Reigate and Banstead Borough Council planners – in 2006.

Neighbours were dumbfounded to discover the farmer, his wife, Linda, 39, and their son Harry, nine, had been living inside for four years, while it was disguised as a giant stack of straw.

Mr Fidler said: "We are determined to take this all the way to the top. We are quite sure that ultimately we will win.

"Our prayer is that commonsense prevails and we are allowed to keep our home.

"It has been traumatic. We are trying to carry on with our lives but this court case is always nagging away in the background."

By the time the castle was unveiled to the world in May 2006, Mr Fidler believed it had become immune from planning control.

Planning law states that if a property is "substantially completed" for four years, it is legally allowed to exist.

However, the Council had other ideas and issued a planning enforcement notice in March 2007 demanding its demolition.

The farmer fought to keep his castle, and a series of other modifications, including a go-kart track, at Honeycrock Farm, in a three-week public inquiry, which concluded in March last year.

The Secretary of State's planning inspector, Nicholas Freeman, however, ruled the castle should come down.

Mr Fidler added: "One thing which has helped us through all of this is the amount of support we have been getting from all over the world.

"People in Australia and America have sent us letters of support, I've even had someone from Scotland invite me up to have a look at his castle.

"Everyone knows about the castle in Salfords now, and not one person has called me to complain about it.

"So why do the Government still want to tear something down, which nobody is opposed to?"

High Court Judge Sir Thane Forbes reserved judgement, and will give a decision in writing, expected before the end of the year.