Thanks for that information. This is something I've never heard of, so perhaps they are unique to America.
Star forts are all over Europe before Europeans were in the Americas. You probably were never interested in military things.
You have several in Florida @Marie Mallery. I think the most visited ones in the U.S. are on the Canadian border.
I am interested in the Roman military. They set up forts throughout England, so we are never far from one. There was a hill-fort not far from where I'm living now, which will have been used by the Celts. I live near the Pennines and the whole area is full of stone circles and ancient ruins.
Here is a link to the website that has the Star Forts in England, @Celia Jenkins . When you click on a name, then it has information about each star fort . http://www.starforts.com/uk.html