Inspiration for Stone Circle came from Stonehenge in the English County Wiltshire, as well as other stone circles, such as Avebury.
In recalling the first time the young actors in the films first saw the stones, art director Alan Gilmore commented "I heard they asked Alfonso if the stones were why he chose the location. It's always gratifying when your work is mistaken for the real thing!"
Since the circle is a sundial, it is possible it was used to adjust the time shown on the Clock Tower's dial should the clock become out of sequence with the actual time of day.
As the Stone Circle appears to be the oldest parts of the grounds it's is possible that this is the spot where the founders of the school found the Hogwarts Pensieve and decided to erect the school here.
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