Shown here are all the major rivers and tributaries of Ireland with their lengths. Starting with the Northern Ireland rivers, and going in a clockwise direction, the rivers are listed in regard to their entry into the different seas: the Irish Sea, the Celtic Sea and the Atlantic Ocean. Also shown are two tables. Table 1 shows the longest rivers in Ireland with their lengths, the counties they flow through, and their catchment areas. Table 2 shows the largest rivers in Ireland in cubic metres per second.