The Alnwick Garden is a complex of formal gardens adjacent to Alnwick Castle in the town of Alnwick, Northumberland, England. The gardens have a long history under the dukes of Northumberland, but fell into disrepair until revived at the turn of the 21st century. The garden now features various themed plantings designed around a central water cascade. The revival of the gardens led to several public disputes between the Duchess of Northumberland and various garden experts concerning preservation and the use of public funds. The garden now belongs to a charitable trust, which is separate from Northumberland Estates, although the 12th Duke of Northumberland donated the 42-acre site and contributed £9 million towards redevelopment costs.

Alnwick Castle is a castle and country house in Alnwick in the English county of 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.