The River Nanny, locally known as the Nanny Water (Irish: An Ainí), is a wild trout river flowing through County Meath in Ireland's Leinster province. Rising near Johnstown village close to Kentstown at an elevation of approximately 55 metres (180 feet), the river winds through the towns of Duleek and Julianstown before emptying into the Irish Sea at Laytown. The Nanny is well regarded among Irish anglers for its stocks of wild brown trout and seasonal sea trout runs, offering classic fly fishing in a pastoral east-coast setting. The river's estuary is also a designated Special Protection Area, reflecting the ecological richness of the broader Nanny catchment.