June 30 is the commemoration of Saint Failbe who is associated in the calendars with the locality of Cell or Cill-Eó. He may or may not be linked to another saint from the same place, Caelán. The Martyrology of Gorman lists ‘holy Failbe and Coelán’ with the note ‘Failbe and Caelán in Cell Eó’.  The two are similarly linked in the later Martyrology of Donegal but in the earlier Martyrology of Tallaght they are listed separately as ‘Coelan Dachoe’ and ‘Falbe of Chill Eó’ i.e. ‘from Cell Éo’.  Canon O’Hanlon deals with them separately in Volume VI of his Lives of the Irish Saints and places Cell-Eó, which the place names glossary in the Martyrology of Gorman translates as ‘the church of the yews’, in County Longford:

St. Failbe of Cill-eo, County of Longford.