The new £18.5 million visitors' centre at the Giant's Causeway has been unveiled as one of the "brightest jewels" in Northern Ireland's tourism crown.
The National Trust opened the doors to the new centre on Co Antrim's dramatic North Coast today. It overlooks the World Heritage Site and features exhibitions on the stories and science behind the attraction.
The Causeway includes more than 40,000 interlocking basalt columns formed by volcanic activity. It attracts around 600,000 visitors a year.
Walks and trails around the landscape have been upgraded and the centre is a model of sustainable building, with a grass-topped roof and harvesting heat from the ground.
First Minister Peter Robinson said: "It showcases one of the brightest jewels in our crown, the only World Heritage Site on this island now has a visitor centre that befits its unique status.
"The remarkable history of these stones and the history of this part of the country can be told using the very latest interactive technology."
The Causeway was formed, in myth and legend, by a battle between two giants. Its real-life tale of geological formation is recalled in a series of displays at the centre.
John Kay, 95, lives near the Causeway. He was a flag boy who used to direct trams between North Coast resorts and the Causeway in 1931 and was paid a tuppence a day.
He met Mr Robinson and Deputy First Minister Martin McGuinness today at the key-turning ceremony.
Commenting on the centre, the pensioner said: "It is very elaborate."