Garden lovers visiting Ireland should not miss Fernhill Gardens in Sandyford.

This was written some time back, but still holds true:

Fernhill Gardens overlook Dublin Bay and are protected by the Three Rock Mountain. The three famous Wellingtonias, set in the dramatic Broad Walk, can be seen by mariners returning home. Dendrologists from all over the World know to add Fernhill to their list of best gardens in Ireland. During the thirty years visiting these beautiful and well loved gardens I have seen every form of wildlife known to Dubliners. A shy and speedy tree-creeper was one of my favourite bird sitings. The deer from the hills above, while welcome, tend to feed with too extreme enthusiasm on the lush perennial foliage under the trees, but are admired by the gardeners who find them a gentle presence. Whenever I need a good gift for a friend I make a bee-line up to Fernhill and am always certain of finding a match for any personality in the lovely nursery attached to the old farm buildings. Today, since Christmas is on the way, the choice was for winter greenery. I bought rosemary just about to flower and and astrantia with perfect white whorls. The mild Autumn means that there are still Kaffir lilies and penstemon in flower out of doors This is an ideal garden for family outings... plenty of picnic tables and a true sense of being wild and free.