Giant's Causeway

The Giant's Causeway (Irish: Clochán an Aifir or Clochán na bhFomhórach) is an area of approximately 40,000 interlocking basalt columns, the result of an ancient volcanic fissure eruption, part of the North Atlantic Igneous Province active in the region during the Paleogene period. It is located in County Antrim on the north coast of Northern Ireland, about three miles (4.8 km) northeast of the town of Bushmills. It was declared a World Heritage Site by UNESCO in 1986 and a national nature reserve by the Department of the Environment for Northern Ireland in 1987. In a 2005 poll of Radio Times readers, the Giant's Causeway was named the fourth-greatest natural wonder in the United Kingdom. The tops of the columns form stepping stones that lead from the cliff foot and disappear under the sea. Most of the columns are hexagonal, although some have four, five, seven, or eight sides. The tallest are approximately 12 metres (39 ft) high, and the solidified lava in the cliffs is 28 metres (92 ft) thick in places. Much of the Giant's Causeway and Causeway Coast World Heritage Site is owned and managed by the National Trust. It is one of the most popular tourist attractions in Northern Ireland, receiving nearly one million visitors in 2019. Access to the Giant's Causeway is free of charge: it is not necessary to go via the visitor centre that charges a fee. The remainder of the site is owned by the Crown Estate and several private landowners.