According to legend, it is where Christ revealed to St Patrick a cave or hole which was an entrance to purgatory.

A crowd of rustics in the home of Saints
They find no sweetness in devotion to poetry,
nor in the ancient generations of their forefathers.

The vengeance of God is the reason for it.
The men of Scotland have settled in their place.
Where have the Gaels gone?

Ulster poem c.1650

"For he whom the living do not glorify with blessings is not a true ruler."

- (Audacht Morainn, 700 AD)

The Old Irish word 'rígdomna' means heir-apparent (lit. 'material of a king'). However this noscript was not a guarantee of election as king, hence the superior noscript of 'tánaise ríg': "one whom the whole tribe looks forward for the kingship without dispute."

IRA Commandant General Tom Maguire was born #OnThisDay in 1892. He was the last surviving TD of the 2nd All-Ireland Dáil Éireann, who refused to recognise the two partition parliaments established in Ireland by Westminster to subvert the National Parliament.

Irish kingship was both ancient & sacred: A king was responsible not only for material prosperity, but the spiritual health of his people.

The early Irish king embodied qualities of excellence (febas); these were not just martial qualities but moral ones bound to good judgement.

On the four modes of kingship in Gaelic Ireland - from the admirable true ruler (fírfhlaith), to the tyrannical bull-ruler (tarbfhlaith).

Cormac mac Airt was the greatest of the Irish pre-Christian monarchs. A philosopher, warrior, & judge, he finds an equal only in Brian Boru.

The 'Teagasc na Riogh' is a book of kingly instruction written by high king Cormac mac Airt. It forms a dialogue between himself & his son:

High king Cormac Mac Airt on the governance of a true nation.

Family, tradition, moral virtue, defense of the people are central:

Monastic ruins of Clonmacnoise - Ireland's 'Valley of the Kings'.

The historical burial place of the high kings of Tara and Connacht.

Niall of the Nine was Ireland's Alexander the Great - Nine hostages from Scots, Saxons, Brits & Franks were paid to him, such was his power.

Up to 3 million men could be descended from Niall of the Nine Hostages, medieval Irish king of the O'Neill dynasty: https://www.newscientist.com/article/dn8600-medieval-irish-warlord-boasts-three-million-descendants/

Irish Kingship ritual - Shows the sacrifice of a white mare & preparation of stew by a tribe of Ulstermen, c. 1220.

The Irish king was expected to have fir flathemon (truth of the ruler); to be righteous, come from high ancestry & capable of heroic action.

Morann macMáin was a legendary judge who instructed ancient Irish kings.

He taught that a king's justice brought abundance, truth, morality.