The castle is located on the promontory of Grignano, just outside the city of Trieste. It was built by Archduke Ferdinand of Habsburg around the mid-1800s on karst rock overlooking the sea and surrounded by a huge park full of numerous botanical species. The castle reflects the pomp and elegance typical of the mansions of the nobility of the time, a combination of different architectural styles: from Gothic to medieval to Renaissance. The park around the castle, some 22 hectares, is the result of a massive transformation of the original rocky promontory. The park houses numerous trees and plants from various parts of the world, grassy spaces and paths, gazebos and ponds, typical of English gardens.

On the hill of the same name stands the castle of San Giusto, whose history dates back to 1000 B.C., thanks to its strategic position controlling the city and the entire surrounding area. To access the castle, one must walk up a ramp that ends at a wooden drawbridge. As you enter, you enter the Piazzale delle Milizie and reach the ramparts through walkways and stairs. In the Lapidarium Tergestino, in the Lalio bastion, there are a number of period tombstone finds.In 1930 the castle became the property of the City of Trieste, which designated it for use for tourism purposes; in fact, it is the site of numerous cultural events, performances and exhibitions. From the castle walls there is a panoramic view of the Gulf and the city of Trieste.