The Giant's Causeway is an area of about 40,000 interlocking basalt columns, the result of an ancient volcanic fissure eruption. It is located in County Antrim on the north coast of Northern Ireland, about 4.8 km northeast of the town of Bushmills.
It was declared a World Heritage Site by UNESCO in 1986 and a national nature reserve in 1987 by the Department of the Environment for Northern Ireland. The tops of the columns form stepping stones that lead from the cliff foot and disappear under the sea. The tallest are about 12 metres high, and the solidified lava in the cliffs is 28 metres thick in places.
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 Fenian Cycle of 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 hides from Benandonner when he realises that his foe is much bigger than he is. Fionn's wife, Oonagh, disguises Fionn as a baby and tucks him in a cradle. When Benandonner sees the size of the 'baby', he reckons that its father, Fionn, must be a giant among giants. He flees back to Scotland in fright, 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.
