sentences:  The necropolis was found on the manmade island of Isola Sacra, which lies between the cities of Portus and Ostia Antica, a region just south of Rome.The emperor Trajan was in power when this artificial island was created.Much of the excavated necropolis flanked the Via Severiana, which ran through Isola Sacra and traveled southeast from Ostica to Terracina.