Built c. 1300, taken by O'Donnell in 1598
Ballymote Castle
Richard de Burgo, the Red Earl of Ulster, built Ballymote Castle around 1300 as the strongest of the de Burgo castles in Connacht — a square keep with a tower at each corner and twin gate-towers. It changed hands often through the late medieval centuries. Red Hugh O'Donnell took it in 1598, the year before the Battle of the Yellow Ford, and used it as a forward base. The castle has been a ruin since the Williamite wars. The walls and four corner towers are still standing. You can walk in off the lane and stand in the middle of it.
A 1391 manuscript that decoded a script
The Book of Ballymote
Around 1391 a group of scribes working in or near the town compiled what came to be called the Book of Ballymote — Leabhar Bhaile an Mhóta. It is a large vellum manuscript of Irish genealogies, hagiography, world history, and translations from Latin. Tucked inside it is the Auraicept na nÉces, a treatise that explains the Ogham alphabet. Centuries later, when antiquarians tried to read the carved Ogham stones standing in fields across the south and west, the Book of Ballymote was the Rosetta they had. The manuscript is now in the Royal Irish Academy in Dublin. The town it was written in is the one you are standing in.
Composer of Maritana, born nearby in 1812
Vincent Wallace
William Vincent Wallace was born in 1812, the composer of the opera Maritana that played London, Dublin and Vienna in the middle of the nineteenth century. He is usually listed as a Waterford man — his family lived there for much of his childhood — but the Sligo connection is local and persistent, and Ballymote claims a corner of him. The opera is rarely staged now. The tunes are still sung in country houses if you know who to ask.