Tomb engravings dating back 6,000 years are among the latest discoveries unearthed on the route of a controversial highway under construction in Ireland.

©Mary Deevy, National Roads Authority
This large stone decorated with engravings dating to the Late Stone Age has been discovered at an ancient site in Ireland that sits in the path of a controversial highway project.


The historic site, at Lismullin in County Meath, was handed over to road builders last month, just weeks after the Stone Age art was found inside a medieval bunker.

The engravings have been removed to allow construction of the highway to proceed.

The new find follows the discovery last spring of a prehistoric open-air temple nearby, causing construction of the 37-mile-long (60-kilometer-long) M3 highway northwest of Dublin to be temporarily suspended (see map).

The timber temple enclosure was found just 1.25 miles (2 kilometers) from the Hill of Tara, once the seat of power of ancient Celtic kings.

The latest excavations at Lismullin revealed part of a huge stone monument, or megalith, decorated with engravings dating to the Late Stone Age, according to archaeologists from Ireland's National Roads Authority (NRA).

Discovered some 165 feet (50 meters) from the temple's enclosure, the stone features a series of zigzags, concentric circles, and arcs.

"It's classic megalithic art," said Mary Deevy, NRA's chief archaeologist.

The engravings are similar to those that decorate other burial chambers in the region known as passage tombs, Deevy noted.

"We've only got half a boulder, but we think originally it was probably a curbstone from a passage tomb," she said.

The stone would have formed a wall that kept the burial mound together, with the artwork displayed on the outer surface, Deevy said.

What the motifs symbolized remains a mystery, the archaeologist added.

Viking Attacks

The stone was discovered within an early medieval souterrain, an underground structure that may have been used by local inhabitants to defend themselves against Viking raiders, the excavation team reported.

Dating to around the 10th century A.D., the souterrain was probably constructed using the broken megalith as building material.

"The souterrain builders robbed or quarried the stone from a Neolithic [Late Stone Age] monument," Deevy said.

"Souterrains are common in Ireland, and it's not unusual to have stones from earlier monuments reused on them," she added.

The rock art will eventually go on public display, according to Deevy, who describes the Lismullin site as "100 percent excavated."

The site was handed over to road builders on December 18, with construction work expected to start soon.

Campaigners who want the highway re-routed away from the Hill of Tara area have attacked the decision.

"Significant damage has already been done," said Vincent Salafia of Dublin-based protest group TaraWatch.

"But until the road is built on top of the site, I suppose there is still hope."

One of the "Top Discoveries"

Irish citizens opposed to the road project are currently fielding legal advice with a view to obtaining a court injunction to halt construction, the campaigner said.

The European Commission has criticized the Irish government for failing to properly reassess the impact of the road project after the ruins of the open-air temple were uncovered last year.

Under European law, the discovery should have triggered a so-called environmental impact assessment, Salafia said.

While the Lismullin site was declared a national monument, "this has made no difference whatsoever," he added.

Upward of 40 archaeological sites have been uncovered along the route of the highway, Salafia said.

"The bigger argument that's at stake is that Lismullin is connected to all these other 40 sites, and that they are all part and parcel of one single large national monument, which is the Hill of Tara complex," he said.

"If a new environment impact assessment were done, that's what would be shown, and that the motorway should go outside that complex rather than straight through it."

Lismullin's timber enclosure site was recently named one of the top ten discoveries of 2007 by the magazine Archaeology, published by the Archaeological Institute of America.

"Construction of the new M3 highway, meant to ease traffic congestion around Dublin, threatens not only the Hill of Tara's timeless quality, but also newly discovered archaeological sites in the surrounding valley," the magazine said.