Today some 120 hectares (300 acres) of the lands of Derrynane, together with Derrynane House, make up Derrynane National Historic Park, under the management of National Historic Properties of the Office of Public Works. The House was officially opened to the public as a museum commemorating Daniel O’Connell by President Eamon De Valera in August 1967 and the surrounding Park was officially declared open by President Cearbhall Ó Dálaigh in August 1975 to mark the 200th anniversary of O’Connell’s birth.