WHEN Stonehenge was erected was Britain part of the continent of Europe? - W Sewell, Bishop Auckland.

WHAT is the history of Stonehenge? Why was it built and are there any good stone circles in the North-East? - Jeff Wilkinson, South Moor, Stanley.

WHEN Stonehenge was erected anyone from Europe wishing to visit would have to cross the Channel. Britain was last connected to Europe by land in 6500BC when rising water flooded all the land now forming the English Channel. This was caused by melting ice caps at the beginning of a warmer period of the Ice Age - a period which we are still experiencing today. The first Stonehenge was not built until 3100BC, at least 3,400 years after Britain's separation from Europe.

This was not the great Stonehenge we are familiar with today, but an earlier earthwork consisting mainly of a circular ditch. This first Stonehenge was in use for around 500 years, when it was abandoned. A new Stonehenge was not built until around 2100BC. Stonehenge 2 consisted of two concentric circles of Blue Stones brought from the mountains of South Wales, 240 miles away. The circles were never completed and the stones were comparatively small, weighing only four tons each.

The stones were built to line up with an approaching trackway now called the Avenue. An early 20th Century astronomer discovered that the Avenue lined up with the point at which the sun would rise on the summer solstice.

It was not until 2000-1900BC that the massive 50 ton stones called Sarsens were erected at Stonehenge to form Stonehenge 3. It is these great stones which impress us so much today.

Stonehenge 3 was built with carefully dressed and smoothed stones forming a great circle topped with a ring of lintel stones. Within the great circle were five separate groups of Sarsens, which collectively formed a horseshoe shape. Each group, called a Trilithon, consisted of three stones, two being upright and one forming a lintel or cap.

Further changes were made to Stonehenge from 1900BC to 1200BC, mostly connected with relocation of the Blue Stones. Modifications were also carried out to the Avenue around 1100BC and this seems to be the last period in which there is any proof of regular activity at Stonehenge.

It was not until 500 years later that Celts arrived with their Druid culture, which is often mistakenly connected with the monument.

There is a strong belief that Stonehenge was used for astronomical observations. Over the centuries, many of the stones were removed for building material and what remains is only a shadow of what it would have been in its heyday.

As for North-East examples of stone circles, there are some minor circles at Duddo in North Northumberland, and some good examples in Cumbria, notably the Castlerigg Circle near Keswick. The circle is older than Stonehenge and is, in my opinion, just as impressive.

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