The Giant's Causeway
On the coast of Northern Ireland, 40,000 stone columns step down into the sea. Legend says a giant built them to reach Scotland.
What was reported
On the north coast of County Antrim, around 40,000 interlocking basalt columns, most of them six-sided, form stepping stones that lead from the cliffs down into the sea.
Irish legend says the giant Fionn mac Cumhaill, Finn McCool, built the causeway to cross to Scotland and fight a rival giant, Benandonner. Similar columns appear across the sea on the Scottish island of Staffa, home of Fingal's Cave.
Explanations offered
Geologists explain that about 60 million years ago, lava flowed across the area and cooled slowly. As it cooled, it shrank and cracked into regular columns, in the same way drying mud cracks into polygons. It is a UNESCO World Heritage Site.
- When
- Formed about 60 million years ago
- Where
- County Antrim, Northern Ireland
- Witnesses
- Visitors and geologists
- Status
- Explained
Famous cases are real, widely reported events. Each file sets out what witnesses said and the explanations that have been offered, without taking a side.