Google Earth Question, What is this?

Question

If you start at The Great Pyramids in Egypt, scroll straight down until you come to a large road, zoom in towards the bottom of the curve in the road. To the lower right of the curve, there is a circle of horseshoe shapes, with a few in the center. There are other similar shapes scattered around the same area. What are these?
I think they are dig sites.

Answer 1

Ancient egyptions used a half cirlce wall that rose towards the ends to match the horizon of the earth. They would mark on it a single star, then follow it all night. They would mark where the star went down on the other side. True north is directly in the middle. This is how they alligned the pyrymids.