Derryiron
Is ainm dó Doire Iarainn
Townland in Knockdrin electoral division, Ballyburly civil parish, Warrenstown barony, County Offaly, Ireland.
Catholic parish: Rhode (Kildare and Leighlin)
1848–1864
Griffith's Valuation
1901
National Census
1911
National Census
1926
National Census