Fodor's Expert Review Howth Castle Gardens

The Howth Castle Gardens, next door to the Transport Museum and accessible from the Deer Park Hotel, were laid out in the early 18th century. The many rare varieties in the fine rhododendron garden are in full flower April through June; there are also high beech hedges. The rambling castle, built in 1654 and considerably altered in the following centuries, is not open to the public, but you can access the ruins of a tall, square, 16th-century castle and a Neolithic dolmen.