Finn McCool, Myths & Legends of the Causeway

The Giant’s Causeway, near Bushmills, has been drawing thousands of tourists from near and far with its mystery and rare geological formations, however, long before modern transport made the journey (slightly) more accessible for travellers to make their way to the County Antrim Coast and the UNESCO World Heritage site situated on one of its most northerly points, people have wondered about the story of how it came to be.

From our article on the Geology of the Giants Causeway here, we know how the Causeways 40000 or so Hexagonal shaped columns were actually created, through Volcanic activity around 60 million years ago.

However, this still does little to take away from the magical atmosphere that permeates around the mighty columns of the Causeway, seemingly adding to the myths and legends that have been passed down from generation to generation told by local storytellers for millennia.

Finn McCool

Finn McCool (otherwise known as Mac Cumhaill in Irish ) was a legendary warrior in Irish mythology associated with the Finnian’s (An Fhiannaíocht in Irish), a tribe of peoples who inhabited Ireland before the Celts. In most tales about this legendary warrior, he is not said to be a giant, however, in the myths around the Causeway, he is made out to be a giant of extraordinary height. Some tales are said he stood 54 feet, or 16 meters, tall.

Ireland, Scotland and the Isle Of Man share mythological stories that have Finn playing a central role. For example in the case of the Causeway, it is sometimes said to be a collection of stepping stones that allowed Finn to travel at will between the Causeway and the Scottish Coast without getting his feet wet

Fionn Mac Cumhaill Early Life

The Boyhood Deeds of Fionn documents Finn Mac Cool childhood. Finn mac cumail (Finn McCool) mother was Muireann Muncháem (Muirne). His grandfather on his mothers side was a druid Tadg mac Nuadat, who lived on the hill of Almu. He had foreseen her marriage would result in losing his home, so spurned any potential suitor. This forced Cumhal, the leader of the feared Fianna warriors who had fallen in love, to abduct her. Outraged at this, Tadg appealed for help to the High King of Ireland, Conn of the Hundred Battles. Conn agreed and forbade the relationship, sending his troops after the newly outlawed Cumhal.

The armies of Conn and Cumhall met at the Battle of Cnucha, and Cath Cnucha Cumhal was slain by Goll Mac Morna (who then became the leader of the Fianna). Muraine was returned to her father by King Conn and was discovered to be pregnant. Outraged and shamed, her father rejected her and ordered his followers to burn her. Conn interjected and instead sent her to the Druidess Bodhmall, who was Cumhal’s sister, and into the protection of her husband Fiacal mac Conchinn.

Muireann gave birth to a son called Deimne. It was evident the boy’s father Cumhal still had enemies, so with a heavy heart, she left her son with Bodhmall in Ballyfin, a small village in Sliabh Bladhma (Slieve Bloom Mountains), Laois. Muirne later married the king of Kerry.

Fionn was brought up by two foster mothers in secret, Bodhmall and her companion Liath Luachra, who were known as great warriors. They hid the boy in the forest and taught him how to be a great warrior and joined him on several adventures. Word of young Fionn’s adventures was beginning to spread, and his foster parents were worried his father’s enemies would find him so confident they had taught him all they could, sent him into the service of local kings to work, but each time he would be recognised as Cumhal’s son. In fear of being unable to protect him, he was forced to move away yet again. It seems this nomadic lifestyle took him South to West Cork to serve the King of Bantry.

Finn Mac Cumhal And The Salmon of Knowledge

The most famous story of young Fionn was met he met the Druid and Poet Finnegas (Finn Eces) near the River Boyne, which is North-East of Ballyfin. It is said young Deimne studied under him so would have likely been after leaving the Slieve Bloom mountains and before heading South to Cork.

The druid Finnegas had spent seven years trying to catch the Salmon of Knowledge which inhabited a pool in the River Boyne. It was foretold that whoever ate the salmon would gain all the knowledge in the world, gained through the fishes diet of holy tree hazelnuts. With Finn’s help, the fish was finally caught, and the boy was tasked with cooking it.

While doing so, Deimne burnt this thumb on the fish and put it in his mouth to soothe the pain. Instantly Finn was given the salmon’s wisdom, and when Finnegas saw this, he gave Finn maccool the rest of the salmon to eat. This knowledge guided Fionn on how to gain revenge against Goll for killing his father. In later stories, it was said he could call on the salmon’s knowledge by sucking his thumb.

Aillen and leadership of the Fianna

In Irish Mythology Aillen (or Áillen) was an incendiary being, who played the harp and sung beautiful songs. Also called the burner, the member of the Tuatha Dé Danann resided in Mag Mell, the underworld. They were thought to be personifications of darkness, chaos, death, drought and blight.

Each year the Gaelic festival Samhain marked the end of the Harvest Season and was celebrated 31st October to 1st November. Much like the modern Halloween, it was essentially a day for the Dead. It was said that the sídhe fairy mounds were always open at Samhain, and these portals to the Otherworld allowed the souls of the dead and the supernatural beings to enter the mortal world. 

This allowed Aillen the opportunity to cross over every year, which he had done for 23 years. Some stories call him a Goblin, rather than a supernatural being from the underworld.

Each year the High King of Ireland hosted a celebration gathering at the capital Tara (County Meath) for the Lords, Nobles and local Kings. And each year the mobile fire-breather Aillen lulled everyone to sleep with his music and burned down the palace of Tara. Makes you wonder why they had the party there in the first place. But one Samhain, young Fionn Mac Cumhail was there. This could have been while serving the King of Bantry, but a version says he was wandering on his travels and saw the party and joined the craic. Either way, he heard the stories of Aillén mac Midgna, and how he put everyone to sleep with his music. Even the fearless Fianna who were guarding the place under the leadership of Goll mac morna. But young Fionn had a trick up his sleeve, well a spear anyway. Legend says he put the spear into flames and pressed the hot blade against his head to stay awake, and drove the weapon into the Tuatha Dé Danann. As a reward for this feat, King Cormac granted anything he desired, and Fionn announced his heritage and requested his father’s leadership of the Fianna which was granted. Another version says this was one of three strenuous tests set by King Cormac for Finn to became the leader of Clan Bascna. Regardless, with his army rightfully behind him, the young warrior addressed his Grandfather Tadg mac Nuadat and demanded compensation for his father’s death. He was given Dun Almhain, the Hill of Allen.

Fionn Mac Cool Later Life

As leader of the feared Fianna, Fionn mac Cumhail had many more adventures documented in other stories in the Fenian Cycle.

The Pursuit of Diarmuid and Gráinne

The aging Fionn Mac Cumhaill was promised the hand of his daughter Gráinne by High King Cormac mac Airt, but at the wedding feast, she falls for the handsome young lieutenant of the Fianna, Diarmuid Ua Duibhne. She forces him to run away with her, perhaps to avoid the married life. Fionn and the Fianna chase them all over Ireland until finally making his peace with the couple. Years later, Diarmuid is gored on a boar hunt, and Fionn has the ability to heal with water drunk through his hands. But each time Finn gathers the water, he lets it slip between his fingers and allows the young man to die. In an alternate version, the marriage is a disaster, and a sad Finn overhears Gráinne tell her father how unhappy she is, so he annuls the marriage and is offered the hand of another daughter Ailbe instead.

The Death of Finn McCool

The legend says that Fionn Mac Cumhaill is not dead, merely sleeping with the Fianna in a cave until the hunting horn of the Fianna, the Dord Fiann, is sounded three times. Then he will return and defend Ireland in the hour of her greatest need. But there are several accounts of his death in the annals of history. The 10th-Century poet Cinead húa Hartacáin maintains that Finn was beheaded by Aiclech mac Dubdrenn in the battle against the Lúagni Temrach, in County Meath. 

The annals of the four masters state Finn was killed the year AD 283, at Rath-Breagh near the River Boyne. Derived from two manuscript fragments it says that Finn lived to old age, but died jumping across the River Boyne when he banged his head off a rock and/or drowned. He is then found by Aiclech who cuts off his head. So same location, the same end result.

Finn MacCool Final Resting Place

To the East of Leitrim sits Sheebeg (Sí Bheag) and Sheemore (Sí Mhór), -hills steeped in mythology with Cairns on the summit and tombs on the accent. Both hills are said to be sidhe fairy mounds and released fairies and spirits on Samhain (Halloween).

It is said this is the resting place of Grainne, lover of Diarmuid, and daughter of High King Cormac mac Airt. Who in some versions of the story married Fionn after the death of her lover, later throwing herself of his chariot to her death.

Local legend say this is the resting place of Fionn Mac cumhaill as the battle of Gabhra was fought between the hills. Although experts think this was between Tara and Skryne in County Meath.

Regardless the Cairns suggest someone noble was buried here. It’s a stunning site, and from the 479 feet tip of Sheebeg, you can see five counties and fourteen lakes so there are worse spots to spend eternity.

The site was excavated in 1931 and the Irish times at the time reported that at at Sheebeg near Carrick on Shannon in a mound known as that of Finn McCool, two human skeletons were found side by side and facing directly towards the Hill of Tara. Definitely male and female, the woman’s teeth were in perfect condition.

Places named after Fionn MacCumhaill

Fingals Cave, Staffa Island

The link to Scotland is in principle to the similar collection of hexagonal columns that appear in a cave on the Scottish Island of Staffa just a short crossing from the North Antrim Coast in Northern Ireland Indeed on a clear day can be seen from the elevated points around the Causeway.

Other stories claim that Finn built the Causeway as a way to get over to The Isle of Staffa and meet a Scottish giant that he was in love with and bring her back to Ireland to marry her.

The most common legend told, however, revolves around a rivalry and an excellent piece of deception.

The Giant’s Causeway

The UNESCO World Heritage Site located in County Antrim, Northern Ireland. The Giant’sCauseway has about 40,000 interlocking basalt columns created by an ancient volcanic fissure eruption. Local myth says it was created by Finn Maccumhail

Finn McCools Fingers

Shantemon Stone Row is a set of five standing stones on the Shantemon mountain in County Cavan, arranged in a south-east/north-west orientation. The nickname comes from the story that Fionn mac Cumhaill lost a hand in battle.

As the video above says, a Scottish giant named Benandonner, otherwise known as the Red Man (an Duine Dearg in Scots Gaelic), was believed to roam the West Coast of Scotland. Mac Cumhaill and an Duine Dearg did not see eye to eye and Finn challenged his Scottish rival to a fight while they shouted and threatened each other from across the Sea of Moyle.

Building a Causeway from rocks he found along the Antrim coast, so he could reach his biggest enemy, Finn completes his new crossing only to find that Benandonner is bigger an enemy in more ways than he first thought.


Upon crossing the Causeway, Finn realises that Benandonner is, in fact, significantly more prominent than he first thought. Recognising this he Instantly regrets making the threats and challenging the Scottish foe to a fight, Mac Cumhaill hoped to make it back to Ireland without being noticed by the Scottish giant. 

Unfortunately for Finn, he is spotted as he makes his way back and Benandonner gives chase to the Irish warriors home, thought to be in Fort-of-Allen in Co. Kildare….although this is some way from The Giants Causeway!

As Finn runs as fast as he can back home to Ireland, he loses one of his boots and sadly this is no Cinderella story, as the boot was to remain exactly where it was and is still visible at the Causeway today.


With the Scottish giant now across the sea and in Ireland, his massive size is even more evident as Fionn and his wife can feel the tremors of him approaching their house, they are forced to plug their ears with moss to deafen out the sounds of the giant’s approaching footsteps.

Fionn, finding himself in a pickle he was unsure he could get out of alive, turns to Oonagh, his wife, who ingeniously saves the day, by wrapping Finn in a sheet and telling him to settle himself into a babies cot. When Benandonner arrives at her door, she welcomes him, apologising that Fionn is currently out hunting deer.

Welcoming the Scottish Giant into her home, she points out the various weapons adorning the walls that she claims are Finn’s but in reality, would be much too large and heavy for a man of Finn’s size to carry.

As is customary in Ireland, she offers to make Benandonner Fionn’s favourite meal while he waits, instead Oonagh cooks a cake of griddle-bread baked with the iron griddle pressed inside it, on which the Scottish Giant breaks three front teeth, and followed this with a strip of hard fat nailed to a block of red timber, on which the giant loses a further two teeth.

With the Scottish Giant starting to feel he’s bitten off more than he can chew, Oonagh then asks if the visitor would like to meet their new baby and the Scot is shocked and terrified when he sees the size of their “son” who is, of course, Finn wrapped up in a sheet.

Assuming his Irish foe is enormous if this is just his child, the Benandonner makes his excuses to Oonagh, and flees back across the Causeway, destroying it in his wake.

As the legend goes, with Scottish Giant in full flight, Fionn is believed to have grabbed a chunk of stone from Antrim and thrown it after him to scare him from ever venturing back to Ireland again. 

The Isle Of Man

The chunk of stone missed, however, and what remains in between is said to be where the Isle of Man comes from. The area where Fionn had taken the stone from later filled with water and is said to have become Lough Neigh, the largest lake in Ireland.

As with so much folklore and legends, many versions are not always told the same way. Some stories saying that Fionn was asleep in bed when Oonagh heard the Scottish giant coming and took it upon herself to hide him.

Other stories we have heard, say that the Causeway was never completed and the rivalry never came to a head as both giants fell asleep from all of the hard work of just building the passageway across the sea of Moyle.

Possibly the most gruesome tale told, however, says that the “baby” Fionn bit off the magic middle finger of Benandonner, causing the giant to lose all his strength, and leave Ireland for good.

Whatever version is told, they make for great stories. Many of these can be seen and heard in the Giants Causeway Visitor Centre.

Have you heard another version of the Giants Causeway Story? Why not tell us and have it written here

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Originally from Scotland, I now reside near the beautiful seaside town of Portstewart, about 10 miles along the the Causeway Coastal Route from the Giants Causeway. By day I works in IT and by day off I spend much of my time travelling around the Island with my young family, writing about my experiences for many sites both locally and nationally.