Lough Derg
Lough Derg is the southernmost of the three main Shannon lakes, stretching 39 kilometres from Portumna at its north end to Killaloe in the south. The west shore - the Clare side - is lower and quieter than the Tipperary shore. The lake is used for sailing, motor cruising, swimming, and fishing; the heronry at Rossmore and the birdlife on the islands are significant enough that parts of the lake have Special Protection Area status. Holy Island (Inis Cealtra), with its 7th-century monastic ruins and four churches, sits in the lake a short ferry ride from Mountshannon.