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Alnwick Castle is a castle and country house in Alnwick in Northumberland. It is the seat of the 12th Duke of Northumberland, built following the Norman Conquest and renovated and remodelled a number of times. It is a Grade I listed building now the home of Ralph Percy, 12th Duke of Northumberland and his family. In 2016, the castle received over 600,000 visitors per year when combined with adjacent attraction the Alnwick Garden.
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Grade I listed buildings and structures are of exceptional, even international importance. There are over 6,000 in the country. Only 2.5% of listed buildings are Grade I listed.
In Scotland the classification is Category A
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