The South Circle was reconstructed by the Time Team in 2005. Their reconstruction was built on flat ground - this model illustrates the challenges of building the same reconstruction on a slope (that is, the challenges faced by the original builders - not by me. I was never further than 50 feet away from a radiator, bed or fridge when I did my version).

Many secrets remain surrounding the creation of Stonehenge. Archaeologists try to unravel the mystery. Stonehenge Decoded: National Geographic Video http://www.youtube.com/natgeo