The Reynolds family built and owned Castle island and Jail island.John built the prison and castle in1570 on the shores of Lough Scur. John was popularly known as Shane.He had become a captain in the Queen's army . To show he was committed to the English ways , he became a Protestant . His action did not meet with the approval of all of his clan. Shane invited all the principal men of the Mc Rannalls clan for a conference to try to persuade them to follow his examples. Shane also had his castle filled with his armed retainers , carefully concealed from his visitors and finding he could not accomplish his purpose, his armed men rushed in on the defenceless guests and butchered them into cold blood . This is how he got his cowardly and shameful name of "Sean na gCeann", which in English means 'Sean of the heads '. In 1632 "Sean na gCeann" charged a staring son of a widow for snatching a small cake from the baker's shop in Kesh. " Sean na gCeann'' had no pity for the boy and sentenced the boy to be hanged.The son's distressed mother heard the bad news and went to beg for her sons life. He ordered her from his presence. The old widowed woman drew a knife which she kept beneath her long cloak. She used the knife and "Sean na gCeann" fell dead to the ground .