When you get to Belmullet follow the signs for the R313, heading south. Its about 20kms from Belmullet, past a bay of Caribbean azure water, right on until you can go no further and you come to the lighthouse at Blacksod Point Latitude 54°05.923' North Longitude 010°03.628' West.
A station was established here in 1864. Apparently the house was damaged by a freak wave in 1989 which seemed impossible on the lovely balmy afternoon I was there. Below, a plaque on the wall commemorates Blacksod's part in the Second World War.