Giant's Causeway

Giant's Causeway


Location: County Antrim  Map

Formation: 50 to 60 million years ago


Description of Giant's Causeway

The Giant's Causeway or Causeway of the Giants is an area that contains some 40,000 basalt columns from the relatively rapid cooling of the lava in a crater or volcanic caldera, which occurred about 60 million years ago. It is located on the northeastern coast of the island of Ireland, about 4.8 km north of Bushmills in County Antrim, Northern Ireland. It was declared a World Heritage Site in 1986, and a National Nature Reserve in 1987. It was discovered in 1693.


The geological process that gives rise to the formation of basalt colonnades is relatively simple: the incandescent lava in a volcanic chimney or in a wash can get to cool in situ when the volcano or caldera ceases in its eruptive activity. This cooling gives rise to the formation of basalt, which is a crystalline rock, although with very small crystals because its cooling was very fast and with a much weaker pressure than that supported by the igneous rocks that lead to the formation of granite at greater depths: in fact, the basalt is formed on the surface of the lava in the crater or caldera and is progressing in depth. As the basalt is formed, its volume decreases and generally hexagonal prisms are formed whose separation compensates for the decrease in its volume (columnar disjunction). Subsequently, the erosion acts first on the surrounding rocks because the basalt is much more resistant, these columns being exposed.


Legend of Giant's Causeway

Legend has it that there were two giants, one from Ireland (Finn) and another from Staffa (Bennandoner), who got along very badly and continuously threw rocks. From so much throwing rocks a field of stones was formed on the sea. The Scottish giant decided to cross the rock road and defeat his opponent, who was stronger than the other. The woman of the Irish giant (Oonagh) saw how the Scottish giant came, so she decided to dress her baby husband. When the Scot arrived and saw that the baby was so big, he thought that his father would be three times as big, so he fled stomping the rocks, so that they would sink in the sea and that the other giant could not reach Staffa.