Aurelian established the Tripolis mint, c. 274 A.D., which minted antoniniani and a few aurei types until it closed during the join reign of Diocletian and Maximian, c. 287 A.D. The Tripolis coins of Aurelian, Tacitus and Probus are not clearly mint-marked to identify Tripolis (most often with "KA" in the exergue). After Probus, Tripolis coins are marked "TR" in the reverse field. There were several cities within the Roman Empire named Tripolis. The most likely city that hosted the Roman mint was the Tripolis south of Antioch, which today is Tripoli, Lebanon. Dates of operation: c. 274 - c. 287. Mintmarks: KA in exergue, TR in center field.