Craigh na Dun does not exist - which is to say the place exists but is not called by that name. There is a stone circle in the hills above Inverness and there are many about. The most famous and the one most likely used for the Outlander story is at Clava Carins, which is very near Culloden, the site of the disasterous last stand of the Jacobites.
Something is not right. This message is just to keep things from messing up down the road