Police ordered hundreds of hippies away from Stonehenge on Saturday in a bid to prevent clashes during midsummer celebrations at the circle of giant prehistoric stones.

The hippies, who had set up camp on Salisbury Plain, west of London, were served with a legal notice ordering them to leave land within six miles of Stonehenge.

Within hours police made a number of arrests in the town of Salisbury when fights involving about 40 people broke out.

Hundreds of officers ringed the monument after a convoy of hippies smashed through a perimeter fence and drove nine vehicles onto a nearby field on Friday. Thirty people were arrested.

Special police protection had been requested by the owners of the monument, the English Heritage charitable group.

Police sealed off roads to the 4,500-year-old Bronze Age circle where robed members of an ancient British sect, the Order of the Druids, traditionally celebrate daybreak on the longest day of the year - next Tuesday.