It is an original rock formation consisting of 37.000 tightly packed basalt columns that were formed during a volcanic eruption 50-60 million years ago. The tallest columns are about 12 meters high. The average width of the basalts is about 46 cm, the height is from 1 to 2 meters. At its widest point, the causeway is 180 meters wide and extends into the sea to a distance of 150 meters.
