When it was built in 1825, Lord Suffield had to mount an armed guard to stop disgruntled workers from destroying it because it was putting them out of work.

Now Gunton Sawmill is protected for a different reason - as a heritage treasure that provides an evocative link to a bygone age.

On Sunday, scores of people visited its tucked away location in the grounds of Gunton Hall to see the mesmerising mill in action - and to celebrate a £69,000 Heritage Lottery Fund (HLF) grant that will give it at least 30 years more of life.

Bagpipes were played as a celebratory cake was marched into the mill to mark the latest chapter in a remarkable story of restoration that began almost 40 years ago with the sawmill run down and almost ruined.

Its re-discovery in 1976 by Norfolk Windmills Trust triggered a 12-year labour of love by volunteers. And in 1988, it was finally possible to use the saw to cut timber using the power of flowing water.

Twenty-five years on, the sawmill was again in danger of falling into disrepair, largely because of a leaky thatched roof that was allowing water to damage the machinery.

But the HLF grant will pay for a re-thatch of the sawmill by A and R Kelly, plus conservation of the timber frame and brick-built mill race.

To add a lovely touch, the main beam for the timber work has been cut on the sawmill, using oak grown at Gunton.

David Doak, one of the volunteers, said the team was 'thrilled' by the grant. He said: 'Gunton Sawmill is a unique and precious survivor from a time when buildings, technology and energy were locally sourced and maintained.

'We are confident that this project will allow us to secure the preservation and continued operation of this wonderful building for a new generation in the 21st century.'

The sawmill nestles in a nook in parkland and has the look of a Hobbit house.

It is arguably Norfolk's most idiosyncratic attraction - and almost certainly its least polished. For, according to its loyal team of volunteers, one of its draws is that it has not been 'sanitised'. It is rough and ready, and comes complete with an uneven floor and a perilously low ceiling.

Stooping through the tiny doorway, you are transported back to its 19th-century heyday.

And long before green power was on the agenda, Gunton Sawmill is the ultimate example of renewable energy. It uses nothing but the power of water to turn the mill wheels and drive the serrated saw up and down.

Volunteer Barré Funnell, who has been helping out since the 1970s, said: 'When I started, it was in a terrible state. I certainly hoped that we'd see it restored, but couldn't be sure.

'It's been hard work, but it's a labour of love.'

The money will also make the sawmill more accessible, enabling volunteers to open it more often to organised groups.

The sawmill was built to take its water power from Sawmill Lake, and was designed to provide sawn timber for the 12,000-acre Gunton Hall estate, although it also has a small grist mill set on the beams within the roof area.

A small brick outhouse stands beside the mill, which was used as a smithy, a rest area and a workshop.

? Visit www.norfolkmills.co.uk