IntellisaurDinoAlien

Try researching the work of Alexander Thom. It depends how ancient you mean really...

These should prove interesting though:

https://www.youtube.com/watch?v=Rgq9SsqdyQA

https://www.youtube.com/watch?v=Mz2tvT8sPgo

http://www.ancient-wisdom.co.uk/stonecircles.htm

FriedBizkit

Thanks for the reply...I will check these out.