Ireland's Eye

A short distance offshore from Howth is Ireland's Eye, a rocky sea-bird sanctuary with the ruins of a 6th-century monastery. There's a Martello tower at the northwestern end of the island, where boats from Howth land, while a spectacularly sheer rock face plummets into the sea at the eastern end. As well as the sea birds overhead, you can see young birds on the ground during the nesting season. Seals can also be spotted around the island.

Doyle & Sons takes boats out to the island from the East Pier of Howth Harbour during the summer, usually on weekend afternoons. Don't wear shorts if you're planning to visit the monastery ruins because they're surrounded by a thicket of stinging nettles. And bring your rubbish back with you - far too many island visitors don't.

Further north from Ireland's Eye is Lambay Island, an important sea-bird sanctuary that cannot be visited.