Nobody quite knows why Stonehenge was built, and that is part of its power. Begun around 3000 BC as a circular ditch and bank, it was remodelled over the following thousand years, and the great sarsen stones, some weighing more than twenty tonnes, were raised around 2500 BC. The sarsens came from the Marlborough Downs, about twenty-five kilometres north; the smaller bluestones came from the Preseli Hills in west Wales, more than two hundred kilometres away, and how they were moved remains one of the great puzzles of prehistory. The monument is aligned with the sunrise at the summer solstice and the sunset at the winter solstice, and thousands gather here at those times. With Avebury and the surrounding landscape, it is a UNESCO World Heritage Site.
The visitor centre is about two kilometres from the stones, with a museum and reconstructions of Neolithic houses; a shuttle bus or a walk across the downs takes you to the circle. You cannot normally walk among the stones themselves, but the path around them gives good views from every side. Book ahead in summer, when it gets very busy.
The surrounding Salisbury Plain is a vast chalk upland, much of it used by the army for training, with tank crossings and red flags warning of live firing. The landscape is open and rolling, with huge skies, skylarks singing over the grassland, and burial mounds scattered across the downs. Larkhill and Bulford are army garrison towns.
The A303 runs right past the stones and is notoriously congested, especially on summer weekends, as it is a main route to the West Country; there have been long-running plans and controversy over a tunnel to bury the road near the monument. The smaller roads around the plain, through the valleys of the Avon and the Wylye, are much nicer, with thatched villages and gentle curves. To the south, Salisbury has a cathedral with the tallest spire in Britain.
Amesbury, three kilometres east, has fuel, shops and pubs, and claims to be the oldest continuously inhabited settlement in Britain. Come early in the morning or late in the afternoon, when the low sun casts long shadows and the crowds are thinner.