NAAS (pron. Nace, as in place), a market town of Co. Kildare, Ireland, 20 m. S.W. from Dublin on branches of the Great Southern and Western railway and of the Grand Canal. Pop. (1901) 3836. It is situated among the foothills of the Wicklow Mountains, close to the river Liffey. The town is of great antiquity, and was a residence of the kings of Leinster, the place of whose assemblies is marked by a neighbouring rath or mound. Naas returned two members to the Irish parliament from 1559 until the union in 1800. Of a castle taken by Cromwell in 1650, and of several former abbeys, there are no remains. Punchestown racecourse, 21/2 m. S.E., is the scene of well-known steeplechases.