Area of a Circle

Dear student,

You are a mathematical explorer sent by your village to discover the unexplained world of circles.  You are to provide mathematical descriptions involving the ancient structures of the world. You are going to explore such structures as: Stonehenge, the Roman Colosseum, and the Costa Rica Stone Spheres. You are to determine the radius, diameter, circumference, and area ofthese structures.  You must also provide a one page description of the structure. 

The essential question that you must answer is, �How do you think ancient people built these structures with such mathematical precision having little or no math background�?