|a promontory of columnar basalt on the N coast of Northern Ireland, in Antrim: consists of several thousand pillars, mostly hexagonal, that were formed by the rapid cooling of lava and the inward contraction of the lava flow|
promontory of basalt columns along 4 miles (6 km) of the northern coast of Northern Ireland. It lies on the edge of the Antrim plateau between Causeway Head and Benbane Head, some 25 miles (40 km) northeast of Londonderry. There are approximately 40,000 of these stone pillars, each typically with five to seven irregular sides, jutting out of the cliff faces as if they were steps creeping into the sea.
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