The three-year long excavation project, which was carried out by Headland Group, a Scottish based firm, is one of the largest in Northern Ireland to date.
Scientists uncovered a roughly 5,000 year-old circular site in the townland of Armaghlughey which contains graves, evidence of timber buildings and burnt pits that bear a strong resemblance to Stonehenge and the Giant's Ring near Belfast, both of which are prehistoric stone circle sites.
At a nearby excavation, the archaeologists were also surprised to find a 6,000 year old pit, with small quantities of human bone and pottery flakes.
A single cremation burial bit with an inverted urn, dated to between 1910 and 1730BC, was subsequently discovered.
It's believed that rituals and ceremonies took place at the site, possibly even sacrifices. One difference to Stonehenge is that the building remains are made out of wood rather than stone.
The archaeologists also found evidence of Christian worship further west of the site where a large early Medieval ringfort or possible ecclesiastical site was excavated.
In total there were 65 sites or areas of archaeological potential on the A4/5, including numerous burnt mounds (prehistoric cooking sites), two ring forts, a prehistoric settlement, a Bronze Age ritual timber alignment and three very large ring ditch enclosures, which were probably burial mounds, and a mill lade.
Following field work, summary reports on each of the sites was produced and submitted to Dr Michael Avery of Archaeological Associates (Ireland) and Kate Robb of John Cronin Consultants.
The Edinburgh based firm of archaeologists said it had ensured that the A4 roadworks proceeded without damaging historical sites and artefacts and where there were unexpected discoveries, recorded and excavated these sites to professional standards.
The team are currently working on the final publication of their findings which should be submitted to the Roads Service in Spring 2010.