The Giant's Causeway, Northern Ireland

The Giant's Causeway (known as Clochán an Aifir or Clochán na bhFomhórach in Irish) is an area of about 40,000 interlocking basalt columns. The formation of the Giant’s Causeway was due to intense volcanic activity. Lava welling up through fissures in the chalk bed formed a "lava plateau". Three periods of volcanic activity gave rise to the Lower, Middle and Upper Basalts, and it's the Middle Basalt rock which forms the famous amphitheatres of hexagonal columns in the Causeway.

It is located in County Antrim on the northeast coast of Northern Ireland, about 4.8 km northeast of the town of Bushmills. The tops of the columns form stepping stones that lead from the cliff foot and disappear under the sea. Most of the columns are hexagonal, although there are also some with four, five, seven or eight sides. The tallest are about 12 metres high and the solidified lava in the cliffs is 28 metres thick in places.

I always like legends.  According to a 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) 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. In one version of the story, Fionn defeats Benandonner. In another, Fionn hides from Benandonner when he realises that his foe is much bigger than he. 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 could not follow.  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.

I am grateful to Nicole (20 March 2014) for sending me this wonderful postcard.  (Postcrossing Direct Swap)