This eastern part of the church was its most sacred. It housed the high altar 

Lit by the distinctive tall pointed lancet windows. Dating from the 1190s, these may be the first such Gothic lancets built anywhere in Ireland and they must have flooded the altar with light. The south wall houses a sedile or seat for the officiating priest or abbot and another piscina. In the north wall is a recess containing a pair of small cupboards. 

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