Kells is the Anglicised version of Caill, meaning loss, or Cuan - Cian and is probably a union of both, meaning the "loss of Cian" or the place where the ancient Irish people lost their ally, the Great Ith Cian, king of Spain (Heberia / Iberia).
The name for Kells, in Irish, is Ceanannus Mor, which is an alternative spelling of Cian aneus Mor and means Great Cian from the South.
Cian, or Ith Cian, which was his full name, was the king of Breogan and Eber (Heberia-Iberia - the Hebrew's land) who was buried here, by his son Lughaidh* "Samildanach" (man of all crafts), after he was murdered by three Canaanite brothers, sons of Tyre - Tyrians (known in Irish legend as the sons of Turenn), whom he had previously driven out of Spain, for which they hated him and is the reason why they murdered him, by stoning him to death.
* Levi.
Ith Cian's son, prince Lughaidh, had left his dad (Ith Cian) and his homeland of Spain with his five ships and had come to Hebernia (the Hebrew's new land) to find some men from Breogan who had already migrated to Ireland and rule over them, which he did in Magh Bregia (Bregmag). Lughaidh had not sent word to his dad about where he went or that he was living in Hibernia (Ireland), and so, after a few years with no news from him, Ith Cian presumed his son was dead.
On her way from Jerusalem to Tara in Co. Meath, Ireland, with Jeremiah the Bible Prophet (Ollamh Fodhla); who was later buried in Cairn T at Loughcrew, nr. Oldcastle, Co. Meath; queen Teia Tephi the daughter of king Zedekiah of Jerusalem had stopped and stayed with Ith Cian and had been adopted by him as his daughter.
After queen Teia Tephi had arrived in Ireland and married Eochaidh the Heremon/Ard ri (High king), she met her step-brother Lughaidh and told him of Ith Cian's distress at believing his son was dead and that he should let his dad, whom she loved dearly, know that he was alive and well.
Weeks later, Teia Tephi (wrongfully deified as the Bo/Bovinda of Irish mythology); Eochaidh (wrongly deified as The Daighda of Irish mythology) and Lughaidh (also wrongfully deified in Irish mythology) were on their way from Tara to Navan Fort near Armagh to see Nuadh of the Silver Hand, who was the king of Ulster, when they bumped into Ith Cian who had received news that his son Lughaidh was still alive and in Ireland and had come to find him.
Ith Cian found out from Lughaidh that there was a rebellion against The Torah and Tephi; so he set off back South, to Howth, to sail back to Spain to bring his army to help his son and adopted daughter Teia Tephi, against the rebels, who were led by Bressail Mac Elatha (known in Irish legends as Bressail Bodibal [Bodibal - Opposer of Bo/Bovinda] who was buried at Dowth, [Dubad in old Irish] which means Darkness).
On his way back to Howth Ith Cian was seen by the three Canaanite brothers, who recognised him; followed and chased him; caught him up and killed him with stones, and then buried him under the stones.
When Ith Cian did not return with his army, his son, prince Lughaidh, went looking for him and found his grave. He then went in search of the three Canaanite brothers; found and slew them; then buried them under the same stones under which they had buried Ith Cian.
The most probable site for Ith Cian's grave would be the highest point in Kells; as that was the custom. You will probably have noticed that the cairns/tombs of people of note are normally built on hill-tops, so that the people will see their tombs when they look around and always remember them and follow the example and high-standards they set them in life.
Until the new Kells Garda Station was built, on ground that was specially and mechanically raised-up above it; against the wishes of the local people; the highest place in Kells was the mound, on the lower half of which Columba's House was built. It is therefore most probable that the mound under the upper-side of Columba's House is the grave of Ith Cian the king of Spain, after whom Kells was originally named Cian aneus Mor.