Mini 3 Stunning Historic Ireland

[Drone Views Media]

Apart from the Mournes I'd say the Republic has a greater amount of rugged scenery, plus it has the Cliffs of Mother, 600ft straight down into the Atlantic. Slieve league ?
I think the closest N.Ireland has to the Cliffs of Moher is Fair Head but there is a substantial scree slope at the bottom which reduces the vertical drop significantly.
That said the coast of east Antrim is beautiful, quite a few places where used in Game of Thrones and then there's the Giant's Causeway.

True about the Cliffs, although I much prefer Slieve League, it's so much quieter.