Where is the actual Hogwarts located?

Hogwarts in the world of Harry Potter cannot be precisely located as the school is hidden by the most powerful spells possible, and is Unplottable. Spells protecting the castle include anti-Apparition and Muggle-repelling charms, which make the castle appear as an old ruin with a sign that says 'Danger, Keep Out.' These spells may be lifted by the Headmaster. Most electronic devices do not work on Hogwarts grounds. All that is known is it is somewhere in Scotland besides a large loch.

In real life, filming for scenes at hogwarts take place at Alnwick Castle and Gloucester Cathedral. The Duke of Northumberland, owner of Alnwick Castle, claims on his website: "We are fortunate and privileged in being a location for Hogwarts School in the forthcoming Harry Potter film." Alnwick Castle is the second largest inhabited Castle in England, the first being Windsor Castle, and has been the home of the Percys, Earls and Dukes of Northumberland since 1309. The earliest mention of Alnwick Castle in the history books appears soon after 1096.