Visitors damaging the Giant's Causeway

Visitors have been urged to stop leaving coins which damage the famous Giant’s Causeway stones.

Some visitors to the Causeway want to leave a token of their visit and jam coins into the joints an cracks of the causeway, but the coins are causing damage and National Trust are urging people to stop, and to leave no trace so that this natural wonder can remain a special for future generations.

A report by the British Geological Survey has concluded that the coins wedged into the joints and cracks in the rock is having a detrimental impact on the basalt rock of the Giant’s Causeway, both aesthetically and physically.

Many coins have a centre of one metal, with a thin coating of another. When coins start to corrode, the steel often corrodes faster and separates from the different metal of the outer layer. The coins here also have accelerated corrosion because they are often soaked in saltwater spray and the mixture of metals means they break down faster. This means that the coins are rusting, and expanding to three times their original thickness, which puts huge pressure on the surrounding rock causing it to crumble. Unsightly streaks of copper, nickel and iron oxides are also staining the stones where the coins are corroding.

With removal of coins expected to cost more than £30,000, the National Trust is appealing to visitors to protect the landmark and “leave no trace” during a visit.

The National Trust cares for more than 40,000 columns at the Giant’s Causeway, which is not only Northern Ireland’s first UNESCO World Heritage Site but benefits from a number of other important designations. They include being an Area of Special Scientific Interest, a Special Area of Conservation, a Natural Nature Reserve and part of the Causeway Coast Area of Outstanding Natural Beauty.

The causeway was created by an a volcanic eruption of basalt lava 60 million years ago, creating the columns which are mainly hexagonal with some columns of four, five, seven, and eight sides. There are over 40,000 interlocking columns in the Giant’s Causeway.

There are also legends that it was formed by an Irish giant Finn McCool to get across the Irish Sea to face his rival, the Scottish giant Benandonner, who tore up most of the causeway to prevent Finn from getting back to Scotland.

Another legend has it that the causeway was built so Finn could meet a Scottish maid he was in love with.