At 709 hectares, this is the largest enclosed park in Europe. Its name derives from the Gaelic fionn uisce, which means «clear water». The land, confiscated by the Crown from Kilmainham Priory in 1543, was enclosed in 1662 by the Duke of Ormond, who introduced a herd of fallow deer which still roam around the Fifteen Acres (actually 121 ha). In addition, the Botanical Garden and Zoological Gardens are found here.