Kildare, county (1991 pop. 122,656), 654 sq mi (1,694 sq km), E central Republic of Ireland. The county seat is Kildare. The region is a flat plain, containing the greater portion of the Bog of Allen, as well as many glacial deposits. The principal rivers are the Liffey, the Greese, and the Barrow. Agriculture is the chief occupation; the breeding of racehorses is also significant. The county is named for the oak ( Cill Dara ) under which St. Bridget constructed her cell. Pre-Christian and early Christian relics remain, including a 13th-century castle and monastery.