Ardgillan is situated on the elevated coastline between Balbriggan and Skerries and is unique among Dublin's Regional Parks for the magnificent views it enjoys.
The park consists of 194 acres of rolling pastureland, mixed woodland and gardens, overlooking the bay of Drogheda.
Ardgillan, meaning high-wooded area, is a sanctuary for many species of mammals and birds.
The Castle, the residence at Ardgillan, built in 1738 consists of two stories over a basement which extends out under the south lawns.
The ground floor rooms of the Castle, accessible to wheelchair users, are furnished in Georgian/Victorian style and include the Morning Room, Dining Room and Library.
The first floor area of the Castle is used for an annual programme of exhibitions and Ardgillan is also the home of a permanent exhibition of maps including the 17th century 'Down Survey of Ireland'.
The gardens are in two main parts, the formal garden to the west of the house and the walled garden to the north west. In 1983 work began on the replanting of the formal garden using the layout of the Ordnance Survey map of 1865. A wide collection of roses have been planted, from species and old varieties around the perimeter, climbing roses on the pergola and 'Hybrid Ts' and 'Floribundas' in the centre beds.The final stage of the development of the Rose garden was the rebuilding of the victoria conservatory, constructed by the Scottish firm 'Mckenzie an Moncur' in the 1880's for the Jameson of 'Seamount', Malahide. When fully completed this will incorporate a Museum of Garden History with access from the Walled Garden. This very fine glasshouse was donated to the Parks Department by Mr & Mrs Tracey, the present owners of 'Seamount'.
Ardgillan was opened to the public as a Regional Park in June 1985. Preliminary works were carried out prior to the opening in order to transform what had been an arable farm, into a public park. Five miles of foothpaths were provided throughout the demesne, some by opening old avenues, while others were newly constructed. They now provide a system of varied and interesting woodland walks, and vantage points from which to enjoy views of the sea and coastline.