Famous examples are to be found at Devenish Island, and Glendalough, while that at Clondalkin is the only Round Tower in Ireland to still retain its original cap. With five towers each, County Mayo, County Kilkenny and County Kildare have the most. Mayo's round towers are at Aughagower, Balla, Killala, Meelick and Turlough, while Kildare's are located at Kildare Cathedral (which is high), and also at Castledermot, Oughter Ard, Taghadoe (near Maynooth) and Old Kilcullen. The only known round tower with a hexagonal base is at Kinneigh in County Cork, built in 1014. The round tower at Ardmore, County Waterford, believed to be the latest built in Ireland (c. 12th century), has the unique feature of three string courses around the exterior.