Alnwick Castle is a historic castle in Northumberland, England. It is the seat of the Duke of Northumberland and has been home to the Percy family for over 700 years. The castle was built in the 11th century and has undergone numerous renovations and expansions over the centuries.

The castle has been used as a filming location for several movies and TV shows, most notably as Hogwarts School of Witchcraft and Wizardry in the Harry Potter films. The castle also houses a collection of artwork and furniture, as well as a museum of archaeology.

The castle's gardens, which were redesigned in the 18th century, are considered among the finest in England. They include a grand cascade, a rose garden, and a treehouse, among other attractions. The gardens also feature several fountains and water features, including the impressive Grand Cascade, which was designed by Capability Brown.

Alnwick Castle is open to the public for tours and events, including medieval-style banquets and falconry displays. Visitors can explore the castle's state rooms and learn about its history and architecture. The castle also hosts a number of events throughout the year, including the Alnwick Food Festival and the Alnwick International Music Festival.