This crenelated and towered stone castle is satisfyingly complete. Most castles still open to the public in Ireland are ruins, but this one stands so solidly, you get the picture -- it's what a castle should be. Founded in the 12th century by Richard Talbot, it was occupied by his descendants until 1973. The fully restored interior is furnished with Irish antiques from the 17th to the 19th centuries. One-of-a-kind historical portraits on loan from the National Gallery line the walls. After touring the house, explore the vast estate, with prized gardens filled with more than 5,000 species of plants and flowers -- it's the perfect place for a picnic on a sunny day. The Malahide grounds also contain the Fry Model Railway museum and Tara's Palace, an antique dollhouse and toy collection. Aspiring ghost hunters may be interested to know that the castle is said to have five resident ghosts, including a jester named Puck, who (while alive) made the mildly threatening vow to haunt the place but harm no one until a male Talbot is no longer in residence.