10 interesting facts about the Giant's Causeway in Bushmills

The unique landscape was formed approximately 60 million years ago during the Paleogene period. Intense volcanic activity caused molten basalt to intrude through chalk beds, forming a vast lava plateau. As the thick layer of lava cooled rapidly, it contracted and cracked into the symmetrical, hexagonal pillars we see today.

According to Irish folklore, the causeway was built by the giant Finn McCool. Legend says he constructed the path to Scotland to challenge his rival, Benandonner. When he realised the Scottish giant was much larger than expected, Finn fled back to Ireland, and the pathway was later destroyed during their epic confrontation.

While exploring the site, visitors can find a large rock formation shaped remarkably like a boot. Tucked away in Port Noffer, this ‘Giant’s Boot’ is said to have been lost by Finn McCool as he fled from Benandonner. Interestingly, the boot is estimated to be a massive size 93.5 in human measurements.

While the columns look like they were carved by hand, they are entirely natural. While most of the 40,000 pillars are hexagonal (six-sided), some actually have four, five, seven, or even eight sides. The uniformity is caused by the cooling rate of the lava, which created a pattern known as ‘columnar jointing’.

In 1986, the Giant’s Causeway was named a UNESCO World Heritage site, the first of its kind in Northern Ireland. It was recognised for its ‘superlative natural phenomena’ and its role in the development of geological science. Today, it remains one of the most studied and visited geological sites in the world.

Located within the ‘Middle Causeway’ is a natural throne-like arrangement of stones known as the Wishing Chair. It has been sat upon by so many visitors over the centuries that the basalt surface has become incredibly smooth and shiny. Local lore suggests that anyone who sits in it will have their wish granted.

The site isn't just about rocks; it is a National Nature Reserve home to rare flora and fauna. You can spot the Narrow Mouth Whorl Snail, a rare species protected under European law. Birdwatchers can also see peregrine falcons, razorbills, and fulmars nesting along the steep, rugged cliffs overlooking the Atlantic.

One of the most striking formations at the site is the Giant’s Organ. Standing roughly 40 feet (12 meters) tall, these particular columns look exactly like the pipes of a massive musical instrument. It is part of the cliff face and serves as a prime example of how the basalt layers stacked over time.

In 1588, a ship from the Spanish Armada called La Girona sank just off the coast near the Giant’s Causeway at Lacada Point. It was carrying a massive amount of gold and jewellery. In the 1960s, divers recovered a legendary treasure trove from the site, which is now displayed at the Ulster Museum.

The geological formation doesn't actually end at the Irish coast. The same basalt columns appear across the sea at Fingal’s Cave on the Scottish Isle of Staffa. This shared geology is what likely inspired the myth of the bridge across the sea, as the two sites are part of the same ancient lava flow.