Sinj is a town in the continental part of Split-Dalmatia County, Croatia. As of the 2021 census, the population was 23,500 people, of which 10,8…Sinj is a town in the continental part of Split-Dalmatia County, Croatia. As of the 2021 census, the population was 23,500 people, of which 10,800 inhabited its urban core. Sinj is known for a knights' tournament of Sinjska alka, which has been held since the beginning of the 18th century as a sign of victory over the Ottoman Empire, and for the shrine of Our Lady of Sinj. The urban center of Sinj is a protected cultural heritage site.