The ancient bones have produced evidence of several suspected murders and one case of leprosy - an extremely rare occurrence in medieval times.

Osteoarchaeologist Carmelita Troy, of Headland Archaeology in Cork, said yesterday she has studied the ancient remains of nearly 1,300 individuals - adult males and females along with children - who were buried at the site at Ardreigh, Athy, in Co Kildare.

It is one of the largest skeleton assemblages in the country.

It is believed the site served as a huge regional cemetery for the south Kildare region from perhaps the 7th or 8th century, with classic Christian-style burials - bodies aligned west to east - taking place right up to the 1400s.

"Through the evidence gathered from the results of these excavations, it was clear Ardreigh was a highly significant medieval site, and one that can be considered to be of regional - and probably national importance," a preliminary report on the site suggested.

While final reports and exact carbon-dating have yet to be completed, the Ardreigh skeleton find is already being compared to important cemeteries at the medieval cathedral at Ardfert in Co Kerry, the Mount Offaly cemetery in south Co Dublin and Ballyhanna in Co Donegal.

"The skeletons from Ardreigh give us an important insight into, and help us understand our national heritage and the people from whom we are descended," Ms Troy said.

The site was discovered as part of the R417 Athy-Carlow road realignment scheme.

Initial inspections were carried out in 1999. Further excavations took place between 2000 and 2003 before work resumed in May 2007, concluding in April 2008.

Two neolithic axe heads, several sherds of neolithic pottery, a Bronze Age cremation pit, and defensive ditches that may date to early Christian times, were found.

But the site yielded vast amounts of Medieval material and the remains of some 1,300 people.

The bones were transported to Headland's office in Cork for detailed study.

Ms Troy has spent the last year studying the bones and said while it has been hard work, it has been a fascinating project.

The remains include male and female adults, some aged between 45 and 60, teenagers, children and even some foetuses - one as young as 20 weeks.

Dozens of adult skeletons displayed signs of arthritis, which would not be uncommon.

However, one person was found buried face down with his hands positioned behind his back. The cause of death could not be established.

Ms Troy said the skulls of five adults had suffered sharp-implement injuries or blunt force trauma, possibly due to a blow from an axe.

One skeleton was found to have had a leg amputated, possibly for medical reasons.

She said the vast quantity of skeletons found at this site allows archaeologists to statistically compare the results with other major medieval sites, and draw conclusions in relation to population profiles, as well as the ages, sex and segregation of the people.

Her work on the project is nearing completion. Her final report will form part of the overall report on the site, which will determine where and how the bones will be stored.