Lacy's Canal was named after Hugh de Lacy, Lord of Meath, who lived in Mullingar, County Westmeath, Ireland in the 12th century. It was constructed in the 18th century and links the town of Mullingar to the northern shore of Lough Ennell. It starts at the rear of the Lynn Industrial Estate and enters Lough Ennel about a mile south of Butlers Bridge. It is crossed by both Butlers Bridge and the Joe Dolan Bridge.