Those cliffs are gorgeuos! Reminds me of what we saw on our ferry from Swansea (Wales) to Cork. No pictures, because I ran out of battery by then (end of a loooong day).
We rented bikes in Dublin and rode to Howth; very pleasant, once we were off the main streets and on the lovely bike path. We had such a good time, my wife wanted to buy a bike back in NYC... which she did! Now we ride together here, albeit below training pace.