Kells Round Tower, Medieval round tower in Kells, Ireland.

Kells Round Tower is a medieval sandstone structure rising from the graveyard of a former monastic site. The tower reaches approximately 26 meters tall and contains nine window openings of two types: five with pointed arch heads and four with lintel openings that provided light to the interior.

Kells was founded as a monastic settlement by Saint Columba around 550 on land granted by Diarmait mac Cerbaill, King of Tara. The abbey was re-founded in the early 9th century by monks from Iona, and the round tower was built in the 10th century. The Annals of Ulster record that in 1076 Murchadh son of Flann ua Mael Sechlainn, king of Temair, was killed in the bell-tower of Cenannas.

The tower's name in Irish records appears as Cenannas, as in the Annals of Ulster entry for 1076 recording the killing of Murchadh ua Mael Sechlainn in its bell-tower. The five high crosses stand nearby: the Market Cross, 3.35 m tall, shows a deer hunt, birds, animals and centaurs alongside religious scenes, while the East Cross was left unfinished, its details added on site.

The entrance door is positioned several meters above ground level and is accessed by a ladder through the monastery graveyard. Visitors should wear sturdy shoes and be prepared for uneven ground and limited accessibility around the site.

Most Irish round towers have four top windows, one per cardinal direction; Kells has five, said to face each of the five roads and town gates. The tower lost its cap, possibly to lightning. The Annals of Ulster record that in 1076 Murchadh ua Mael Sechlainn, king of Temair, was killed in the bell-tower of Cenannas.