Derg

Lough Derg is a long lake on the River Shannon, stretching between the hills and lowlands of western Ireland. The river enters at its northern end and leaves near Killaloe in the south, making the lake part of a great inland waterway. Near its western shore lies Holy Island, or Inis Cealtra, a place of churches and an ancient monastic settlement. Its religious importance endured into the early seventeenth century, when Pope Paul V included it among Irish shrines to which he attached an indulgence.