They form a horseshoe open to the Summer Solstice sunrise, a gateway to the Otherworld for the Sun God under whatever name.
This video comes from Otherworld Northeast, a paranormal research organization that set up the video in the allegedly haunted basement of the Literary and Philosophical Society in Newcastle upon Tyne.
I'd say that 50% of the time that I finish an Otherworld novel, I haven't clearly decided who will narrate the next one much less determined a plot.
I can say that the next 2 Otherworld ones are Savannah's.
Where they live is a bit disputed, but it is either on hills, woodlands, underwater or as spiritual beings in an otherworld type of existence.