Land Trust chief executive Euan Hall said: "One of the main aims of the Banks Group and the Blagdon Estate when creating the land sculpture was for her to act as a tourism gateway to Northumberland.
"This first event will showcase the best of Northumberland," he said of stall exhibitors, which include Bamburgh Castle and Kirkley Hall Zoo. "It will be the first of many to be held at this unique venue."
Northumberlandia shaped like a reclining female figure was designed by landscape artist Charles Jencks and is more than seven times the size of a football pitch and taller than an eight-storey building at its highest point.
The Princess Royal officially opened the landscape in Cramligton at the beginning of September but it has been open only on specially selected days. It has been nicknamed the Lady of the North and sits in a 19ha public park run by the Land Trust.
Blagdon Estate and the BanksGroup spent £3m on Northumberlandia and its adjacent watercourses, which took two and a half years to build by Banks using 1.5m tonnes of stone, clay and soil from the adjacent Shotton Surface Mine.
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