Irish archaeologists have identified two prehistoric henge enclosures larger than Stonehenge and possibly as old. They also believe that site, just south of Limerick City, may be the lost location of Tara Luachra, a place famed in early Irish epic literature.
     The henges (defined as such by having a ditch inside an outer bank, like Avebury and the first period of Stonehenge) lie on Friarstown Hill, known locally as Tara Hill.
     The enclosures of Friarstown were first detected on aerial photographs more than 30 years ago. They were thought at the time to be hill forts, but according to Eamon P. Kelly and Tom Condit both "have a large substantial outer bank and arethus more likely to belong to the henge or ceremonial enclosure group of monuments"
     The smaller enclosure, on the limestone summit, is 140 by 120 metres, slightly larger than Stonehenge, with banks on both sides of the ditch. The larger henge, some 40 metres to the east on a secondary summit, is 165 by 157 metres, exceeding in size even the great circle at Stanton Drew in England.
     The proximity of the two Limerick enclosures to each other suggests a ritual rather than defensive function. While a Neolithic date of around 2500 BCE is possible by comparison with English henges, there are other, later enclosures on Tara Hill, most likely to be early Christian or medieval date.
     There is the possibility that the hill may be the elusive site of Tara Luachra, "Tara of the Rushes", named in the epic poem Mesca Uladh, "The Intoxication of the Ulstermen".
Only further prospection and excavation are likely to yield afirm answer, although the recent discovery of a defensive ditch at the more famous Tara near Dublin is an indication that ritual sites may well have been involved in the internecine warfare celebrated by the Irish annals.

Sources: The Times, Archaeology Ireland