Woodhenge is so-called because it was originally a wooden structure of a type similar to Stonehenge. It was probably set up during the Bronze Age c.2000BC for ceremonial use. The concrete posts mark the positions of the original timbers, evidence for which was obtained by evacuation. The rings are oval, with the long axis aligned on the midsummer sunrise. A bank with a ditch on the inner side surrounded the monument, which was entered by a causeway to the north-east.
Oddly enough, this is a little visited site, 'just round the corner' from Stonehenge. It's not as spectacular as Stonehenge, but has a lot of feeling. Sitting quietly in the centre, I found it very easy to pick up evidence of people from the past moving around in sandalled feet. The stones marking the position of the long gone wooden posts lend themselves to experimental rambles in different patterns!! Woodhenge is in Wiltshire.