North Bull Island, Dublin 5

Bull Island or more properly North Bull Island is an island located in Dublin Bay in Ireland, lying roughly parallel to the shore off Clontarf (including Dollymount), Raheny, Kilbarrack, and facing Sutton.
The island, with a sandy beach running its entire length, is a relatively recent, and inadvertent, result of human intervention in the bay.
In times past, Dublin Bay had a long-running problem with silting, notably at the mouth of the River Liffey. After years of primitive dredging, an attempt to maintain a clear channel more effectively was begun when, in 1715, the first piles were driven of what was to become the Great South Wall, completed in 1830.
This barrier was breached by storm action some years later, and in 1761, a stone pier was commenced, working from the Poolbeg Lighthouse, 1768, back to shore, the construction of massive granite blocks being completed in 1795.
The island continues to grow and it is a possibility that within the next half-century continued deposition may lead to its merging with the mainland at Red Rock in Sutton, forming a lagoon, changing the make-up of the area's wildlife and landlocking two dinghy sailing clubs. However, the risk of this is considered small due to the strength of currents and depth of water in Sutton Channel.