The Cliffs of Moher were impressive, but made slightly less so by the fact that the entire area is fairly well developed with paved paths and a snazzy visitor center. The cement didn't mix well with mother nature, and detracted from the experience for me. After that experience, the Slieve League Cliffs were a welcome change. You have to drive up a small, windy, gravely road bordered by sheer vertical drops to get to the parking area on the top. From there, you can hike around the tops of the cliffs along a multitude of trails. There are no signs warning you that "cliff edges are dangerous" nor cement walls blocking you from peering over the edge. A human being's natural aversion to falling from great distances serves as warning enough, and it's more thrilling to tap into these underused instincts. Given that these cliffs are billed the "highest sea cliffs in Europe", these instincts serve very well indeed. Walking along the paths is quite fun, as the slopes wind in steep, odd directions, and the scale of the landscape feels quite surreal. Almost feels like walking around in a Dr. Seuss book. Unfortunately, it was incredibly windy when we were up there, so we didn't get a chance to explore very far. I'd like to revisit when the weather is better. In my opinion, this is the most spectacular natural sight in Ireland.