Northern Ireland’s only UNESCO World Heritage Site consists of some 40,000 hexagonal basalt columns, which jut from the North Channel along the edge of the Antrim Plateau.
Legend has it that the Irish giant Finn McCool built the causeway across the channel so that he could meet his foe, the Scottish giant Benandonner, who had challenged him to a fight.
According to geological studies, the Giant’s Causeway first formed as a lava plateau when molten rock erupted through fissures in the earth. During a period of intense volcanic activity about 50 to 60 million years ago, differences in the lava cooling rate caused the columns to form, while further weathering created circular formations nicknamed “giant’s eyes.”
Despite modern science’s explanation, visitors still delight in the local lore. If you look closely, you can make out traces of Finn McCool in the causeway’s rock structures such as the Giant’s Boot, the Wishing Chair, and the Organ.
Related Link: http://en.wikipedia.org/wiki/Giant%27s_causeway