The girth of their gnarled trunks ranges from 4.4 metres (14 feet 4 inches) to 6 metres (19 feet 8 inches). Today two of the Sweet Chesnuts still stand at around 14m high but the third now mostly comprises a 6m high stump after it was lost in 2012.
The trees might well have been around when Mary, Queen of Scots paid a visit to the island in 1547. Accompanied by her mother, Mary of Guise, the four-year-old infant queen sought refuge at the priory for three weeks following the English victory at the Battle of Pinkie. A poem penned by the Reverend W M Stirling in 1815 recalls the royal visit:
Those giant boughs that wave around
My aged hoary head,
Were then the tenants of the ground
Where walked the royal maid.
DID YOU KNOW? The author, socialist and nationalist politician Robert Bontine Cunninghame Graham (Don Roberto) and his wife are buried in the ruined chancel of the priory.