Channel 4’s Grand Designs doesn’t land too often in Ireland but in 2012 it aired a particularly unusual story about a West End actor’s long journey to revitalise the ruins of Cloontykilla Castle in Co Roscommon. The actor behind the story was Sean Simon, born in Roscommon, who used to play around the fairy tale castle ruins beside Lough Key as a child. Built in 1839 as a folly in the Rockingham estate, once home to the Anglo-Irish King-Harmon family, it was previously used as a hunting and fishing lodge. Its design is sometimes attributed to renowned British architect John…