Brief synthesisThe Giant’s Causeway and Causeway Coast is a spectacular area of global geological importance on the sea coast at the edge of the Antrim plateau in Northern Ireland. The features of the Giant’s Causeway and Causeway Coast site and in particular the strata exposed in the cliff faces, have been key to shaping the understanding of the sequences of activity in the Earth’s geological history. Criterion (viii): The geological activity of the Tertiary era is clearly illustrated by the succession of the lava flows and interbasaltic beds which are in evidence on the Causeway Coast. The extremely regular columnar jointing of the Tholeiitic basalts is a spectacular feature which is displayed in exemplary fashion at the Giant’s Causeway. The Giant’s Causeway World Heritage Site Management Plan acknowledges the continuing effects of natural erosion which will gradually alter the cliff exposures.