Satellite navigation systems are threatening a historic landmark which stood steadfast during the English Civil War.
The North Bar in Beverley, East Yorkshire, is being damaged by lorries whose drivers are following route instructions through the narrow archway as the shortest way into the town.
The 600-year-old structure survived when King Charles I made the town his headquarters as his Cavaliers attempted a siege on Hull in 1642.
Now a sign diverting truckers away from the arch has been installed by East Riding Council and concerned councillors hope to get sat nav companies to mark the route as unsuitable for lorries.
A council spokesman said: "To help alleviate the problem of heavy goods vehicles attempting to use North Bar Within as a through route, we have installed a new sign at the junction of North Bar Within and Hengate, in a bid to steer lorries away from the structure.
"Also the council will try to speak to satellite navigation software programmers to ask them to update their maps. It is hoped that North Bar Within can be marked as unsuitable for HGVs because of its low bridge and Hengate can be shown as the appropriate route for HGV traffic heading out of the town."
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