The largest lough, by area, in Ireland is Lough Neagh. It is situated on a 600-acre peninsula between Castle Hume Lough and Lower Lough Erne. This scheme ensures safe passage for young eels between Lough Derg and the Shannon estuary. A second extensive lake system is centred on Lower and Upper Lough Erne in Fermanagh. The biggest lake is Lough Corrib. There is also the Ardnacrusha canal connected with the Ardnacrusha dam south of Lough Derg. This area contains the village of Mountshannon on the north-western shore of Lough Derg. Islandmagee is a peninsula separating Larne Lough from the North Channel. To the north of Lough Erne, the oldest rocks in the county are found. It sits on the north shore of Belfast Lough, from Belfast. Columbanus left home to study under Sinell, Abbot of Cleenish in Lough Erne. It is one of the largest of the wooded islands along Lough Corrib. Its location provides unobstructed views of the city of Belfast and Belfast Lough. Final exercises were carried out to the south in Dundrum Bay and Belfast Lough. The village lies close to the shores of Lough Allen.