Many of the 700,000 or more people who visit Stonehenge in the west of England every year already have an image of it in their mind's eye before they arrive.
After they leave, many retain memories of its mysterious, haunting shapes, and are apt to reflect long and hard on the seeming miracle that created the double ring of stones in such a bleak and isolated spot so many years ago.
But according to the report of a British parliamentary committee two years ago, primitive visitor-facilities and general neglect of the site make Stonehenge ''a national disgrace.''
In November, a conference in Salisbury, capital of Wiltshire county, where the monument is located, will attempt to chart a better future for Britain's most important prehistoric site, which dates back to the Bronze Age.
So far, a plan to improve the site and isolate the famous stones from the thousands of cars and trucks that roar past it every day only a few yards away, has been mired in bureaucratic inertia and interdepartmental bickering.
Jocelyn Stevens, chairman of English Heritage, a state-funded body charged with safeguarding the nation's treasures, says he is ''incandescent with anger'' at the government's failure to take seriously the need ''to give Stonehenge the care and attention it desperately requires.''
Present tourist arrangements leave much to be desired, to put it mildly. Stonehenge stands on a tiny triangle of ground where two busy highways intersect.
A ramshackle parking lot contains a ticket office, a stand-up eating facility, and a few portable toilets.
To approach the monument from the parking lot, visitors - half of whom come from overseas - must buy a ticket costing $5, then walk through a damp and dingy concrete underpass and emerge onto a roped-off pathway often strewn with litter.
The stones of the monument suddenly confront one, and on a summer day when dozens of buses rumble in from England's big cities, it is easy to be jostled by parties of tourists.
One gets little chance to examine - still less appreciate - the spectacle of the towering, austere stones set against the flat expanse of Salisbury Plain.
Two or three years ago, attempts to put things right at what Unesco in 1984 designated a World Heritage Site were opposed by local residents. David Parker, a councillor in nearby Salisbury, said an English Heritage plan, published in 1990 to upgrade Stonehenge, would ''turn it into a theme park.''
Others objected to suggestions that one of the roads passing by the site should be closed and a half-mile access road be built, leading to a full- fledged visitor center.
The idea of English Heritage's Roy Swanton, who helped devise the plan, was that visitors could arrive at some distance from the site, then take a leisurely stroll to the stones, with plenty of time to appreciate one of the world's richest archaeological landscapes along the way.
But local councillors said the scheme would create traffic congestion. Roy Canham, the Wiltshire county architect, complained that the access road would threaten 9,000 square yards of flint tool debris and broken pottery thousands of years old.
The locals won the argument, and English Heritage had no option but to go back to the drawing board.
Its latest, more ambitious plan proposes that the traffic which currently whizzes by on the surface should be diverted into tunnels, leaving the site virtually clear.
Mr. Stevens and his planners now want to locate the visitor center two miles away, and take people to and from it in small coaches or electric buggies. Instead of peering at the stones from ground level, they could observe them from the brow of a low hill.
From there, they could also get a better idea of the context in which the stones - the largest is 21 feet high - were erected. Stevens says the surrounding area includes more than 400 minor monuments of great interest.
English Heritage claims that under the new scheme the number of people visiting Stonehenge could be doubled, with less crowding than now. It might even be possible to build a hotel well away from the monument.
So why is the plan getting nowhere?
The answer is money. It would cost an estimated $50 million to fulfill Stevens's dream, and Prime Minister John Major's government says that much of money in a cash-strapped economy simply is unavailable from official sources.
English Heritage has an answer to that. Earlier this year, Britain's first national lottery started up. It has been so successful that upwards of $300 million of the profits each year will be available to support the arts, cultural activity, and other good causes.
A bid for national lottery funds is already being prepared by English Heritage, but suddenly a new problem has arisen.
Without consulting his organization, Stevens says, Britain's Transport Department announced on Sept. 19 that it plans to upgrade one of the main roads that currently runs beside Stonehenge.
The present road carries 15,000 to 20,000 cars a day. Some forecast a doubling of that traffic 20 years from now.
Tony Duke, the Transport Department's projects director, says: ''We are not promoting any particular route, but we are showing the public the routes we have investigated.'' Mr. Duke says English Heritage's tunnel proposal is ''not feasible on grounds of cost.''
But not only would the upgraded surface road be a visible and audible intrusion, says Peter Addyman, president of the Council for British Archeology, such road improvement could not be done without disturbing prehistoric sites in the area around the monument. Mr. Addyman says a tunnel could be built for less than the cost of a mile of urban motorway.
Meanwhile, there are signs the government will come under pressure to slice through the red tape and interagency infighting that leaves Stonehenge, in the words of one English Heritage official, a ''touristic slum.''
English Heritage hopes that public pressure will increase in the run-up to the November special conference to consider the future of the site.