25km to Letterkenny we cross the border with Northern Ireland. Unfortunately, in the United Kingdom, the means of payment are still the British pound. 100km further we reach Bushmills, known by the Irish whiskey of the same name. The distillery produces three different types of whiskey. The house brand Bushmills Original, the Black Bush and the Single Malt.

Just 5km east of Bushmills lies the Giant's Causeway. He leads for about five kilometers along the cliffs and ends in the sea, from which he reappears again on the Scottish coast as Fingal's Cave. The Giant's Causeway consists of approximately 40,000 uniformly shaped basalt columns that are 60 million years old. About half of the columns have a hexagonal cross-section.

The largest of the stone pillars are twelve meters high. Geologists attribute the formation of the basalt dam to the cooling of hot lava. Formations of vertical basalt columns can be formed with very slow and even cooling of lava. The volcano, whose lava led to the formation of the Giant's Causeway, has now disappeared from erosion.