Opatija Circuit, also known as Preluk Circuit, or alternatively the “Circuito di Abbazia” (transl. Opatija Circuit), and the “Circuito di Carnaro” (transl. Kvarner Circuit), was a motorsport street circuit in Opatija, Istria, Croatia, which from 1969 to 1977 hosted the Yugoslavian Grand Prix of the motorcycle racing world championship.