Tullamore (tŭl'umôr) [key], town (1991 pop. 9,430), seat of Co. Offaly, central Republic of Ireland. It is a marketing and processing center for a fertile farm area. The Book of Durrow, a copy of the Gospels, was written c.700 at nearby Durrow Abbey (founded 553 by St. Columba; torn down 12th cent.).