Former Taoiseach Mr John Bruton TD has urged the National Roads Authority (NRA) to examine whether it is prudent to route the proposed M3 motorway through the Tara-Skryne valley in Co Meath.
"We have seen the delays in the M50 caused by the controversy surrounding a comparatively common and insignificant archaeological structure - the remains of Carrickmines Castle," the Meath TD said.
"Recent archaeological studies suggest that Tara - which is globally unique - is not just the monuments on the hill itself, but is the centre of a sacred space of interlinked monuments stretching over a comparatively large area."
Noting that the proposed M3 would bisect this area, he said: "Short of the motorway actually going over the Hill of Tara itself, it is difficult to conceive of a route more likely to run into delays generated by archaeological excavations than this one."
In a letter to the NRA, Mr Bruton pointed out that the route had been "identified from the very outset as the least desirable from the archaeological point of view".
And though it had been approved, this did not mean it was the right decision.
Even at this late stage, he suggested in a letter to the NRA, it should consider picking one of the other routes for the motorway.
"I realise that this is not an easy thing to contemplate, but in the long run it could prove to be a much less expensive option."
The former Taoiseach said his concern as a local TD was that the proposed motorway, which would run from Clonee to Kells, should be provided as quickly as possible.
"My worry is that going ahead with this route may not prove to be the quickest."
