World Heritage Site
10 Minutes from Glass Island
According to legend, the columns are the remains of a causeway built by a giant. The story goes that the Irish giant Fionn mac Cumhaill (Finn MacCool), from the Gaelic mythology, was challenged to a fight by the Scottish giant Benandonner. Fionn accepted the challenge and built the causeway across the North Channel so that the two giants could meet.
Fionn defeats Benandonner. The vanquished giant flees back to Scotland, destroying the causeway behind him so that Fionn would be unable to chase him down.
Across the sea, there are identical basalt columns (a part of the same ancient lava flow) at Fingal's Cave on the Scottish isle of Staffa, and it is possible that the story was influenced by this.
In Irish, the Giants Causeway is generally known as Clochán an Aifir (in Rathlin Island Gaelic) or Clochán na bhFomhórach (the Stepping Stones of the Fomorians). It was also known as Tóchar na dTréanfhear (Causeway of the Strongmen). Because of the shape of the overall rock formation, the Giants Causeway has consistently been associated with the concept of a stepping stone or causeway of the Gods (or other mythological creatures/heroes) and most of the folklore tales tend to be linked in some way with this striking physical characteristic.
Fionn mac Cumhaill &
The Giant's Causeway
Around 50 to 60 million years ago, during the Paleocene Epoch, Antrim was subject to intense volcanic activity, when highly fluid molten basalt intruded through chalk beds to form an extensive lava plateau. As the lava cooled, contraction occurred.
Horizontal contraction fractured in a similar way to drying mud, with the cracks propagating down as the mass cooled, leaving pillar like structures, which are also fractured horizontally into "biscuits". In many cases the horizontal fracture has resulted in a bottom face that is convex while the upper face of the lower segment is concave, producing what are called "ball and socket" joints.
The size of the columns is primarily determined by the speed at which lava from a volcanic eruption cools. The extensive fracture network produced the distinctive columns seen today. The basalts were originally part of a great volcanic plateau called the Thulean Plateau which formed during the Paleocene.