On the coast of Northern Ireland, 40,000 mysterious columns of stone rise out of the sea like huge stairs. The unusual rocks cover a length of beach about 5 kilometres long! They are called the Giant’s Causeway.
Ancient stories tell about a king who built a causeway of stepping stones between two countries. The stones joined Ireland and Scotland and had to be large enough for giants to walk on them.
It is not surprising that people long ago invented such a story, because the real stones on Northern Ireland’s coast are very strange. Each measures about 46 centimetres across the top. And every one of them has six sides. They look as if they must have been made by human beings, but they were not. They were made by a volcano.
Long ago, magma exploded from deep inside the earth. As it cooled, it shrank into a hard rock called basalt. As it became cold, the rock split into long columns.
In Northern Ireland, the columns have six sides, but basalt columns found elsewhere may have only four or five sides. A whole cliff of basalt columns can be found in central California, U.S.A. It is called the Devil’s Postpile and looks like a giant’s supply of fence posts.
Picture Credit : Google
