A la Ronde, at Exmouth, is opening its doors for free as part of National Heritage Open day

Scores of free activities are planned for the day in the grounds, including Willet and Patteson with their portable camera obscura, Life in Silhouette, a performance walk with Katie Etheridge and a sale of secondhand books.

John Folkes will be signing copies of the book he has edited featuring the full wartime diaries of Esther Rowley, Dogs, Cats, Bulbs and Bombs – An Exeter and Exmouth wartime diary.

There will also be a tasting tent where visitors can sample local produce, ranging from Lyme Bay wine and Otter beer to fudge, chocolate, biscuits and carrot cake made with flour from the National Trust’s Clyston Mill on the Killerton estate.

A spokesman said: “Car parking is limited, so we are encouraging our supporters to travel by public transport. There is a free gift for everyone arriving by green transport, including on foot.”

Garden games – croquet, quoits, noughts and crosses, tumble tower and snakes and ladders - will be free to use. There will also be an exhibition and sale of work by local artist Helen Melland.