Tilurium was an ancient settlement and military site located at Gardun above the modern town of Trilj in Croatia. Originally an Illyrian hill-fort of the Delmatae tribe, it later became a major Roman legionary fortress and continued as a fortified post into Late Antiquity. Tilurium occupied a plateau on the northeast side of the Cetina River, strategically commanding the river crossing known as Pons Tiluri, the Tilurium Bridge. The site covered approximately 12 hectares, and the modern village of Gardun sits over its remains.