sentences:  Áth Cliath was centred on the crossroads formed by the intersection of the Slige Midluachra and Slige Mhór.After the introduction of Christianity a wayside chapel dedicated to St Mo Lua appears to have been erected at this junction, though the earliest reference to such a church is of a much later date.Another early church, dedicated to St Columba, occupied the site of the present Church of St Audoen, which is thought to be the city's oldest surviving church site.