Of the 60-odd Irish round towers remaining, in various states of repair, 5 are to be found in County Mayo. Round towers are believed to have been built around the 8th to 12th Centuries and were most probably bell towers associated with the church that would have stood alongside. Famously, they have a doorway set several metres above ground level and a few window slits inserted into the stone walls higher up. Window slits tend to be dispersed one per floor, with four at the top floor, in under the conical roof. The top floor windows tend to be larger than the others on the way up, presumably to let the sound of the bell be better heard and are generally (more or less) set in the cardinal directions.
While presumably primarily for bell ringing, I can easily imagine these early medieval monks spending time alone in one of the tiny upper floors, crouched beside the single window slit to one side, a lit candle to the other, perhaps reading scripture or working on a new codex. I admit I can less easily imagine the towers being used as hideaways, in case of attack.
Round Towers of County Mayo
Mayo’s round towers are at Aughagower, Balla, Killala, Meelick and Turlough.
Aughagower : Standing 16m high, this partial tower had a second door cut into it at ground level in recent centuries, allowing the visitor to access it and look up into its interior. It is roofless. Extensive ecclesiastical ruins adjoin this tower.
Killala : Mayo’s finest extant tower stands 26m high and occupies a site bang in the middle of this medieval North Mayo fishing village. Its (repaired) conical top remains.
Meelick : Despite being without its roof, but at 21m high, this remains an impressive tower in a lovely rural setting. There is a very fine inscribed cross slab at its base.
Visit this excellent website that describes all of Ireland’s remaining round towers.