HILL OF TARA, Ireland -- This grassy, windswept hill outside Dublin was long the spiritual and political center of Ireland, an earthen fort where Celtic chieftains jockeyed for power and legend says St. Patrick confronted paganism.
Today, the Hill of Tara is at the center of another showdown -- over whether Ireland, a rapidly expanding country where construction often uncovers the past, can reconcile its rich heritage with the demands of modern life.
Capping two years of arguments, the government authorized archeologists yesterday to begin excavating 38 sites along the proposed route of a new highway past the hill. Environment Minister Dick Roche and some state archeologists say the road project will uncover historical material that otherwise would remain buried. But an alliance of environmentalists, archeologists, and other academics warn that the road will scar Ireland's most significant landscape.
''The Hill of Tara is our ancient, sacred capital. It was the ceremonial center of Ireland for 4,000 years. It was there even when the Celts arrived 2,000 years ago," said Muireann nDi BhrolchDain, lecturer in medieval Irish studies at the National University of Ireland, Maynooth.
The plan to route a four-lane tollway within a mile of the hill, she said, ''is like deciding you will preserve St. Peter's Cathedral but drive a motorway through the square."
A steady stream of tourists comes to the hill, where they wander the gently undulating, grass-covered contours of what was once a fort of short, earthen, circular walls.
There's not much else left to see. Infamously, British zealots tore up the site in 1901-02 in a vain quest for the Ark of the Covenant, causing untold damage that is hidden today by the grass.
Now it's a place primarily for the imagination, reflecting on myth and history from centuries past -- when rival chieftains held summits to pick ''high kings" of Ireland; when St. Patrick, in the fifth century, lit a fire that attracted Tara's druid leaders to hear his sermons on Christianity; and when Daniel O'Connell led a rally in 1843 to oppose British rule.
The campaign against the road has drawn celebrity backers, including actor Stuart Townsend, the Dublin-born boyfriend of Oscar-winning actress Charlize Theron. Townsend has persuaded Theron to sit for a portrait to be auctioned off as a fund-raiser, even though she has yet to visit Tara.
Edel Bhreathnach, a University College Dublin archeologist who has been studying Tara and the surrounding fields for 15 years, called the site ''a ceremonial landscape of the utmost importance, not just to Ireland but to the world."
''If another nation was proposing to do this," she said of the highway, ''we'd be calling them barbarians and Taliban and the rest of it. Yet that's what's happening here."
But much of workaday Ireland sounds fed up with such arguments. To them, the Hill of Tara is a church with a St. Patrick's statue next to fields of grazing sheep -- and a few miles beyond that, one of the country's worst daily traffic jams. The new M3 motorway would connect Dublin, which is home to a third of Ireland's 4 million residents, with the northwest suburb of Navan, County Meath, where housing for 30-somethings is less unaffordable.
Navan commuters can spend more than two hours trying to reach Dublin, 30 miles away, along a single-lane road that becomes gridlocked in the village of Dunshaughlin. A group called ''Meath Citizens for M3" said its survey of 318 households near the hill indicated that 285, or 90 percent, want the road to go through.