Giant’s Causeway (Northern Ireland).
Giant’s Causeway is an area of about 40,000 interlocking basalt columns that interlock to form what looks like a walkway fit for a colossus, the result of an ancient volcanic eruption. The Giant’s Causeway located in County Antrim on the northeast 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.
The stones, mostly hexagonal in shape (although there are also some with four, five, seven or eight sides), formed 60 million years ago when underground lava flows cooled into formations as tall as 39 feet (11.9 meters) high and 18 inches (45.7 cm) in diameter. It was comparatively recently (about 15,000 years ago) that the soil around the seaside stones eroded and they became visible above ground.