Located within the vast grounds of Malahide Castle, these gardens enjoy relative tranquillity even when the castle is rammed with summertime visitors. The Walled Garden (guided tours only, Wednesdays at 2pm) has a fine collection of rare plants from Australia and New Zealand.
The conservatory, designed for an old convent in the 1800s and rescued from destruction, is an excellent import. Another must-see is the old Rose Garden; though surprisingly short of these flowers, it compensates with lovely magnolias and other bright blooms. There's also a lily pond and an enclosed nursery known as the Chicken Yard. Summer is the best time to visit, but even in winter, thanks to careful and imaginative planting, there's always something to see.