Giants Causeway

169340,000 columnsUK (Northern Ireland)

CountryUK (Northern Ireland)

RegionAntrim

Discovered1693

Size/Depth40,000 columns

About Giants Causeway

40,000 interlocking basalt columns formed by ancient volcanic activity. Most are hexagonal. Legend says the giant Finn McCool built it as a bridge to Scotland. A UNESCO World Heritage Site. The tallest columns are 12 m high. Formed about 60 million years ago.

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