|Met:||T13, L195, T41|
|Now part of:||R473, R486, N67, R487, R488|
Starting just south of Ennis, this route followed the River Fergus and then the Shannon using what is now the R473 as far as Kilmurry Mcmahon. It then stayed closer to the coast than the current route, following what is now the R486 for its full length, and so picking up the N67 route. At Kilrush the L51 multiplexed with the T41 for 13km as far as Kilkee, where it reemerged to follow the modern R487 and then R488 to its terminus at Carrigaholt.