in Ancient Geography, a city of Cilicia in Asia Minor, close to the frontier of Syria, on or near the head of the Sinus Issicus, now the Gulf of Scanderoon or Iskenderum. It was in the neighbourhood of this city that Alexander annihilated the Persian army under Darius, n.c. 333. Here, too, was fought, in A.D. 194, the bloody battle between Septimus Severus and Pescennius Niger, in virtue of which the former became sole master of the Roman empire. The exact site of Issus has not yet been discovered. It has been often sought for by modern travellers, and much has been written about it, to little purpose. The disappearance of all remains can only be accounted for on the idea that they have been engulfed by the sea. About 7 miles S.E. from the Syrian frontier, Col. Chesney found some considerable ruins, consisting of the remains of a temple, part of the Acropolis, and an extensive aqueduct, which he believed to belong to the ancient Issus. It is more likely, however, that these mark the site of Nicopolis, a city built by Alexander to commemorate his victory over the Persians.