Alnwick Castle

Alnwick Castle blends cinematic fame with living history as the second-largest inhabited castle in England, welcoming 350,000 visitors yearly. It outperforms #7 Bamburgh Castle in annual foot traffic by 30%, thanks to its starring role as Hogwarts in Harry Potter films. The Alnwick Garden next door features a Grand Cascade with 120 water jets, a horticultural draw for 500,000 garden visitors annually that is unmatched by any other castle on this list. The Percy family has lived here for over 700 years, making it more personal than pure ruins like Caernarfon Castle.