The Ribble begins at the confluence of the "Gayle Beck" and "Batty Wife Beck" near the viaduct at Ribblehead, in the shadow of the Yorkshire three peaks. It is the only major river rising in Yorkshire which flows westward. It flows through Settle, Clitheroe, Ribchester and Preston, before emptying into the Irish Sea between Lytham St. Annes and Southport, a length of . Its main tributaries are the Hodder and Calder which join the river near Great Mitton, the River Darwen which joins at Walton-le-Dale and the River Douglas which joins near Hesketh Bank.