Many places claim to be Arthur's final resting place, but the most prominent of these is Glastonbury Tor. This steep hill in the once-flooded Somerset Levels is said to be the ancient Isle of Avalon, in Celtic folklore the island of enchantment. The hill is said to contain a secret magical passage to the underworld, where King Arthur is sleeping, but will awake in England's hour of need and come to her rescue.
Sounds like another possible Spitfire site too....