County Offaly (Irish: Contae Uíbh Fhailí) is a county in Ireland. It is part of the Midlands Region and is also located in the province of Leinster. It is named after the ancient Kingdom of Uí Failghe and was formerly known as King's County.
Offaly is the 18th largest of Ireland’s 32 counties by area and the 24th largest in terms of population. It is the fifth largest of Leinster’s 12 counties by size and the 10th largest by population. It is the largest county by area and the second largest by population in the Midlands.
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 out across the county with the Bog of Allen extending into four other counties.