I've been reading an excellent book about poetry and architecture in Anglo Saxon England, and Heysham is mentioned many times. Lori Ann Garner explains that the reason for the location of St Patrick's Chapel is clear. The views that we so enjoyed on Saturday would also have provided excellent visibility and security for worshipers. She goes on to say "however, beyond, and likely because of, the obvious security and visibility offered by such a location, elevated architectural sites in the textual and poetic record connote an inherent nobility and positive aura that transcend sheer military advantage."
We certainly felt the "inherent nobility and positive aura" of St Patrick's Chapel, as well as St Peter's Church.