Alnwick Castle is the second largest inhabited castle in England. the residence of the Duke of Northumberland, built immediately following the Norman conquest, and renovated and remodelled a number of times. It is a Grade I listed building.

Special exhibitions are housed in three of the castle's perimeter towers. The Postern Tower, as well as featuring an exhibition on the Dukes of Northumberland and their interest in archaeology, includes frescoes from Pompeii, relics from Ancient Egypt and Romano-British objects. Constable's Tower houses military displays like the Percy Tenantry Volunteers exhibition, local, volunteer soldiers raised to repel Napoleon's planned invasion in the period 1798-1814. The Abbot's Tower houses the Regimental Museum of the Royal Northumberland Fusiliers.

Other facilities open to the public including Knight's Quest (formerly Knight's School), Dragons Quest, the Gift Shop, the Courtyard Cafe and restaurant; The Sanctuary at the Castle.

The castle is used as a stand in for the exterior and interior of Hogwarts in the Harry Potter films (though the wide angle images are computer generated). It has previously been a location used in Becket, Blackadder I, Robin Hood Prince of Thieves and many others listed in the Location section of the Alnwick Castle website.

Also attached are the wonderful Alnwick Gardens.