JSR Farming Group celebrated the milestone birthday by throwing a family friendly bash at Southburn House, which included a hog roast, pig racing and fairground attractions.

Company director Tim Rymer said they wanted to mark the occasion but did not know quite how until coming up with this idea.

"My father got particularly aggrieved about the harvest supper each year so he would suggest a family sports day," said Mr Rymer.

Sunday's event, which was well attended despite the wet weather, also included a display of machinery through the ages and a 'pignic' walk round the Southburn estate.

The event also coincided with the official opening of Southburn Archaeological Museum. A former stable block has been converted into a museum housing more than 1,000 artfects ranging from the pre-historic to the Roman-British to the Post-medieval periods found in and around Southburn farm.

The collection was started in the 1960s by the late Brian Hebblewhite, a tractor driver at Southburn farm, who began picking up pieces of pottery and artefacts while at work.

With the support of the late John Rymer and archaeologist Tony Brewster, Mr Hebblewhite, his wife Valerie and daughter Ann carried out extensive excavation work on the farm.

Three years ago the Southburn Archaeological Musuem project was launched with the help of more than 50 volunteers, many of whom are members of the East Riding Archaeological Society, with the intention of making the collection available to the public.

Valerie Hebblewhite said the official opening was a proud moment for her and something her late husband would have been pleased to see.

"It's nice to see it all come together like this, I never thought it would. It's taken a long time but it's looking great."

Daughter Ann explained: "I'm the one who used to go walking with my dad, which I enjoyed especially when I found something. Now when I see it like this I feel proud and my dad would have been really proud of it. For Christmas I bought my mum a metal detector so we can keep adding to the collection."

The museum includes an area for youngsters to have a go at digging up artefacts from sand trays, making their own clay pots or mosaics and the volunteers hope the museum will become a regular attraction for school visits.

The museum was opened by Carol Rymer and one of John Rymer's grandchildren, seven-year-old Polly Shaw, who cut the ribbon before joining many other youngsters to enjoy the fun day.