Plans to extend an archaeological protection zone around the Hill of Tara, in Co Meath, were abandoned after it became clear that the proposed M3 motorway would run through it.
An archaeological report by Dr Annaba Kilfeather of Margaret Gowen and Company, compiled in August 2000, explicitly referred to "an expansion of the zone of archaeological protection afforded to Tara".
Largely as a result of the research carried out under the State-funded Discovery programme, "the extent and number of the archaeological monuments in this region has been greatly expanded," the report said.
"This in turn has led to an expansion of the zone of archaeological protection afforded to Tara, which now encompasses not only the hill itself, but also includes an area approximately six kilometres in diameter."
Dr Kilfeather's report was compiled as part of a route selection study by consultants Halcrow Barry for the Dunshaughlin-Navan section of the M3. It was commissioned by the National Roads Authority (NRA) and Meath County Council.
The report said the monuments around Tara "cannot be viewed in isolation, or as individual sites, but must be seen in the context of an intact archaeological landscape, which should not under any circumstances be disturbed".
For these reasons, "the only unreservedly recommended route" would run east of Skryne because "it avoids the area of highest archaeological potential . . . and has the inestimable advantage of being largely invisible from the Hill of Tara".
Minutes of a meeting in April 2000 between Dr Kilfeather, three Halcrow Barry representatives and Mr Brian Duffy, chief archaeologist at Dúchas, as it then was, show that the more easterly route was also Mr Duffy's favourite.
"This was good advice, but it fell on deaf ears," said Mr Conor Newman, lecturer in archaeology at NUI Galway, who carried out the research for Discovery with his colleague, Mr Joe Fenwick, and UCD-based historian Dr Edel Bhreathnach.
Mr Newman said he was one of the people consulted when the expanded protection zone was being designed. "I do not know what protocols have to be implemented in order to set such a zone up, so it may not have been written in stone.
"However, it is recorded in the document [ compiled for the route selection study]," he said. "In short, the zone expanded and then mysteriously contracted to the point where the chosen route is now outside it. Funny that, isn't it?" In a paper last April, Dr Bhreathnach, Mr Fenwick and Mr Newman said Dúchas had redefined the protection zone in 1997-'98 with the intention of imposing archaeological conditions on all planning applications falling within it.
This expanded zone, an ellipse some 6 km in diameter, had been acknowledged in the NRA's environmental impact statement on the M3, as was "the fact that the proposed motorway transgresses it," they wrote.
Even the more restricted zone of archaeological protection around Tara covers a larger area than the State-owned land on the hill - a recognition, the three scholars maintain, of the need for some level of heritage monitoring.
As the restricted zone was "primarily a planning guideline and is not intended to define or describe the limits of the Tara complex, . . . the question of whether the proposed road occurs inside or outside this zone is largely irrelevant."
The NRA, in its defence of the M3, said its route "sought to avoid the important core zone around Tara" by running east of the N3. The motorway would also be further from the Hill of Tara than the existing Dublin-Navan road.
Commenting on the NRA's defence, Mr Newman likened it to "a doctor telling you that your wife is dead but the bus swerved to miss her". The M3, he said, was "going to carve a new furrow, 50 metres wide, through the valley."