Roman Catholic Diocese of Ardagh and Clonmacnoise from the currently-used names) Roman Catholic Diocese of Ardagh and Clonmacnoise The Diocese of Ardagh and Clonmacnoise () is a Roman Catholic diocese in Ireland. The diocese is entirely within the Republic of Ireland and contains most of counties Longford and Leitrim, with parts of counties Cavan, Offaly, Roscommon, Sligo and Westmeath. The main towns in the diocese are Athlone, Ballymahon, Carrick-on-Shannon, Edgeworthstown, Granard and Longford. The union of the sees of Ardagh and Clonmacnoise, which had been proposed in 1709, was carried into effect following the death of Stephen MacEgan, Bishop of Meath on 30 May 1756, who had
County Offaly the county before joining Brosna near the town of Ferbane. The Grand Canal also runs across the county from Edenderry on the north-east to Shannon Harbour before joining the Shannon. The county contains many small lakes from Lake Boora to Pallas Lake and it also contains 42 hectares of swamp land. There are a number Eskers in the counties landscape including Esker Riada. Offaly largely comprises a flat landscape and is known for its extensive bog and peatlands. There are many large bogs in Offaly including the Bog of Allen, Clara bog, Boora bog and Raheenmore Bog which are spread