ATHY, urban district, County Kildare, Ireland, 45m. S.W. of Dublin on a branch of the Great Southern railway. Pop. (1926) 3,549. It is intersected by the river Barrow, the crossing of which was disputed from earliest times, and the name of the town is de rived from a king of Munster killed here in the 2nd century. There are remains of Woodstock castle of the 12th or 13th cen tury. White castle, built in 1506 and rebuilt in 1575, is still occu pied. Both defend the ford. There are also an old town gate and ancient cemetery with slight monastic remains. Previous to the Union, Athy returned two members to the Irish parliament. There are good water communications, by a branch of the Grand canal to Dublin, and by the river Barrow, navigable from here to Water ford harbour.