It was once a lavish piece of 'monastic bling' showcasing the wealth of one of Norfolk's richest monasteries – and now it is to be saved after centuries of decline.

The medieval gatehouse at Pentney Priory, near King's Lynn, survived Henry VIII's reign when all around it was lost, only to crumble in the years that followed.

Now the grade I-listed building, at serious risk of collapse, has been thrown a �200,000 lifeline by English Heritage and an ambitious two-year project to restore and preserve it for future generations has been launched.

Owners Howard Barber and Dita Lee bought the property in 2010 and have started emergency structural repairs with a view to opening it and a new visitors' centre in mid-2013.

Several phases of work will be needed over the coming months, beginning with the construction of a temporary roof – missing since the 18th century – more scaffolding to support the walls and urgent masonry repairs to the crumbling parapets.

'It's a massive responsibility,' Mr Barber, a former airline pilot, said. 'I don't think we realised quite what a responsibility it was – not just the building itself but what it means to the local community and, indeed, the national community.

'We have found that we don't actually own the gatehouse – everybody does.

'Soon, we started to look at the building in a different light and, like falling in love with someone, we came to see just how fabulous it was.

'We had been here for about six months when we realised something needed to be done and we started to explore possible sources of funding.'

Pentney Priory was founded by Robert de Vaux in 1075, the time of William the Conqueror, and once included several monastic buildings including a grand church.

The gatehouse provided luxury accommodation for high-status visitors and their entourages as well as security for the monastery.

'It was built to be a piece of monastic bling and was very lavish inside,' said Robert Parkinson, from English Heritage.

'It was a demonstration of status.

'This was a very wealthy area and the land was very fertile.

'The monastery was making a lot of money and it was that kind of wealth that became so attractive to Henry VIII.'

Pentney Priory was disbanded in 1537 as part of the king's dissolution of the monasteries and the buildings fell into decay while the surrounding farmland was sold off.

More than 800 monasteries were dissolved, demolished for building materials, sold off or reclaimed as Anglican churches during that time.

'It could have survived because it had some kind of economic or functional purpose,' Mr Parkinson said.

'It's possible it was used as a house.' Legend has it that Oliver Cromwell and his men, in flat-bottomed boats armed with guns and a cannon, used the buildings as target practice and the gatehouse was, luckily, just outside their range.

The building has been on the 'at risk' register since it began in 2008 and work to restore it finally began in February following a �200,000 English Heritage grant for the emergency repairs.

'We would like it to become a real focal point for the area,' Mr Barber added.

'We want to bring it back to life and give it back to the community.'

daisy.wallage@archant.co.uk