Lough Derg is the largest lake on the River Shannon and the third largest lake in Ireland, stretching over 30 km in length and up to 15 km wide at its broadest point, covering more than 13,000 hectares. Situated at the southern end of the Shannon system, the lake is bordered to the north by relatively flat agricultural land, while the lower reaches are flanked by the Slieve Aughty Mountains to the west and the Arra Mountains to the east — a dramatic setting that makes it one of the most scenic and productive fisheries in the country. Long regarded as the best fishing lake in Ireland, Lough Derg supports a diverse mix of species and angling styles, drawing everyone from casual recreational anglers to seasoned experts. The towns of Killaloe and Ballina, located approximately 25 km from Limerick city and 50 km from Shannon Airport, serve as the primary hub for anglers visiting the southern end of the lake.