PLANS to build a £35m science and innovation centre next to Oxford’s Castle Mound have been scrapped, we can reveal.

The Magnet was to have been a landmark building attracting 150,000 visitors a year.

But it will not be going ahead, following opposition from heritage groups unhappy that the striking new building would spoil views of the mound and mean the demolition of the 100-year-old Oxford Register Office.

Science Oxford, the charity behind the scheme, had considered scaling down the scheme, dropping designs for a world-class planetarium.

But faced with a drastically reduced scheme, the charity has decided the Magnet is no longer a viable proposition.

Science Oxford had spared no expense over six years in its bid to deliver an iconic building next door to Oxford Castle to celebrate science in Oxford and provide a home for 50 small businesses.

Designs were produced by Foster & Partners, whose work includes the German Reichstag and Beijing Airport. The scheme would have seen the demolition of Macclesfield House, an unloved office block in New Road.

Steve Burgess, chief executive of Science Oxford, said: “The decision has been taken because of a combination of factors. Planning restrictions have limited the use of the site.

“A crucial part of the plan was to acquire the Register Office from Oxfordshire County Council. However, it has became clear the earliest this would be available would be mid-2016.”

With the charity receiving no central Government, council or Lottery support, he said the delay and need for a new application, would have added significantly to the cost.

The original plans submitted to Oxford City Council led to objections about the impact on the mound, one of Oxford’s most historic sites, from English Heritage and Oxford Preservation Trust.

Mr Burgess said Science Oxford could still consider creating a science and innovation centre if a suitable site could be found.

But he said that it would not be going it alone, and would be looking for financial partners in any future scheme. No decision has been taken about the Macclesfield House site, which the trust acquired from the county council for £3.5m. Mr Burgess said there would now be little incentive to pull down the 1960s building, which, as the existing Oxford Centre for Innovation, houses more than 20 firms.

Ian Hudspeth, leader of Oxfordshire County Council, said: “The council was really excited by the plans for the Magnet and had supported Science Oxford in their work to make the vision a reality. ”

Debbie Dance, director of Oxford Preservation Trust, had said of the original Magnet plans: “The Mound is just too important for such treatment.”

But Ms Dance and the trust were much more supportive of the revised proposals.

She said this week: “We have worked closely with Science Oxford. We are disappointed that we won’t see the site redeveloped and will continue working with them.”