Siscia, now Sisak, Croatia, was one of the most important places in Roman Pannonia. It was at confluence of two navigable rivers, the Colapis and Savus, which carried considerable commerce. Siscia was captured by Tiberius, in the reign of Augustus. Tiberius did much to enlarge and embellish the town, including digging a canal to form an island, enhancing the fortifications. It became the central point from which Augustus and Tiberius campaigned against the Pannonians and Illyrians. Pliny mentions Siscia was made a colonia at that time. In the time of Septimius Severus it received fresh colonists, after which it was called Col. Septimia Siscia. When Diocletian split Pannonia into four provinces, Siscia became the capital of Pannonia Savia. It contained the mint and treasury, and was the station of the small fleet kept on the Savus. Siscia maintained its importance until Sirmium began to rise: as Sirmium rose, Siscia declined. The mint master at Siscia was called the procurator monetae Siscianae. Mint dates of operation: c. 262 - 283. Mintmarks: S, SIS, SISC, SISCPS.