The day after stopping in Cork Ireland we were in Belfast Northern Ireland. This was our only stop in Northern Ireland and we wished we could have had more time to explore Belfast. As it was, we really only saw it on the way to and from Giant's Causeway.
For our Belfast stop we'd booked a tour to the Giant's Causeway, a UNESCO world heritage site since 1986. This is a area with roughly 40,000 interlocking basalt columns around an hours drive from Belfast.
Much of the interest behind Giant's Causeway is the story behind its name. The legend is that the Irish giant Finn MacCool was challenged to a fight by the Scottish giant Benandonner. Finn then built the causeway to enable him to cross the water between Ireland and Scotland. There are at least two stories on what happened then. The simple story is that Finn beats Benandonner.
The second, and more elaborate story (leave it to the Irish to generate a lot of Blarney) is that Finn, realizing Benandonner is much larger than him, runs and hides. His wife disguises Finn as a baby. Benandonner then tries to find Finn and finds him disguised as a baby, but thinks it's Finn's son, not Finn himself. Seeing such a large "baby", Benandonner thinks the father must be even larger and runs back to Scotland in fear, destroying the causeway behind him so Finn can't follow.