11 hours ago
Cold hard facts behind henges that mark summer solstice
At exactly 3.42am on Saturday the summer solstice occurs at the moment when the northern hemisphere reaches its greatest tilt towards the sun, resulting in the longest day and shortest night of the year.
Stonehenge is the best-known prehistoric monument for marking the summer solstice. Viewed from the centre of the stone circle, sunrise on the horizon at the solstice is marked by the outlying Heel Stone, and as the sun passes behind the stone several minutes later it casts a long shadow into the heart of the stone circle.
But there are many other, less well-known ancient monuments marking the summer solstice. About two miles from Stonehenge is the site of Woodhenge, built at about the same time as Stonehenge in about 2500BC. It was formed of six concentric oval formations of standing timber posts, surrounded by a bank and ditch. This oval arrangement of the timbers was aligned northeast to southwest, the same as Stonehenge, and would have given a clear view of the summer solstice sunrise towards the northeast horizon.
Another ancient timber circle was Seahenge, discovered in 1998 on the north Norfolk coast at Holme-next-the-Sea. Shifting sands on the beach revealed the gnarled tops of 55 ancient wooden posts placed close together with a huge upturned tree stump in the centre of the circle. Originally the site would have been built on a saltmarsh, with the tide coming in and out from the sea, but over time layers of peat preserved the lower parts of the timbers from decay. A similarly mysterious timber circle dating to the same period lay some 300ft away.
By analysing the tree rings in the wood, the timbers were estimated to have been felled in the spring of 2049BC, and a new theory suggested that the two timber circles were built during a bitterly cold period of climate 4,000 years ago. Severe winters and late springs would have put the prehistoric people at that time under huge stress, and because the timbers at the henges were aligned with sunrise on the summer solstice they may have been designed to extend the summers and bring on milder winters.
