Cius
Cius was an Ancient Greek city bordering the Propontis, in Bithynia and in Mysia. The city was later renamed to Prusias after King Prusias I of Bithynia, who once restored the city.
Etymology
According to the Greek Geographer Strabo in his book Geographica, the eponym of the city is, according to a founding myth, a companion of Heracles who is also the founder of the city. Greek author Apollonius of Rhodes provided another origin, in Argonautica, that the city of Cius was named after a nearby river and was founded by the Argonaut Polyphemus.History
During the Ionian Revolt, Cius was captured by the Persians under their general Hymaees on their counter-offensive against the Ionians that had marched on the capital of the Persian Satrapy of Lydia, Sardis, during the Ionian rebellion. Sometime during the Cretan War, King Philip V of Macedon put Cius, that was then a member of the Aetolian League, under siege. He then razed the city down and ceded it to King Prusias I of Bithynia, who assisted him in capturing Cius. Prusias later restored it under the name Prusias.According to numismatist Katja I. L. Sommer, during the Roman rule, Cius issued a revert back from the name Prusias around the reign of Emperor Claudius at the latest, possibly in order to gain autonomy, and was later renamed back to Prusias during the Flavian period. It was a member of the Delian League. It was an important chain in the ancient Silk Road and became known as a wealthy town.
Geography
Cius was strategically placed at the head of a gulf in the Propontis, called the Gulf of Cius, or Cianus Sinus. Historians Herodotus and Xenophon both reverred to it as Cius in Mysia. Naturalist Pliny the Elder reports that Cius was a Milesian colony. It was at the foot of Mount Arganthonius, which Strabo claimed as the place where Hylas was kidnapped by the Nymphs in a myth. Pliny mentioned the rivers Hylas and Cius here, one of which reminds us of the name of the youth who was stolen by the nymphs, and the other of the mythical founder.The Cius may be the channel by which the lake Ascania discharges its waters into the gulf of Cius; though Pliny speaks of the Ascanium flumen as flowing into the gulf, and we must assume that he gives this name to the channel which connects the lake and the sea. If the river Cius is not identical with this channel, it must be a small stream near Cius. As Ptolemy speaks of the outlets of the Ascanius, it has been conjectured that there may have been two, and that they may be the Hylas and Cius of Pliny; but the plural ἐκβολαί does not necessarily mean more than a single mouth; and Pliny certainly says that the Ascanius flows into the gulf. However, his geography is a constant cause of difficulty. The position of Cius made it the port for the inland parts, and it became a place of much commercial importance. Pomponius Mela calls it the most convenient emporium of Phrygia, which was at no great distance from it.