A number of paths cross this 22 hectare park, which is home to wild oak, pine and cedar forests, as well as an extraordinary selection of orchids, grottos, springs, lakes and waterfalls. The ruins of Aymerich Castle contribute to the magical atmosphere. The castle, originally built in 1053 in order to protect the boundary between the giudicati of Arborea and Cagliari, two of the four kingdoms composing mediaeval Sardinia, later became the official residence of the local marquis. They left the castle in the mid-19th century to occupy the palace, which now is home to the Menhir Museum - Sardinian Prehistoric Sculpture Museum.