Strabo Geography 7.4.7

[7] In addition to the places in the Chersonesus which I have enumerated, there were also the three forts which were built by Scilurus and his sons—the forts which they used as bases of operations against the generals of Mithridates—I mean Palacium, Chabum, and Neapolis. ¹ There was also a Fort Eupatorium, ² founded by Diophantus when he was leading the army for Mithridates. There is a cape about fifteen stadia distant from the wall of the Chersonesites; ³ it forms a very large gulf which inclines towards the city. And above this gulf is situated a lagoon ⁴ which has salt-works. And here, too, was the Ctenus Harbor. Now it was in order that they might hold out that the besieged generals of the king fortified the place, established a garrison on the cape aforesaid, and filled up that part of the mouth of the gulf which extends as far as the city, so that there was now an easy journey on foot and, in a way, one city instead of two. Consequently, they could more easily beat off the Scythians. But when the Scythians made their attack, near Ctenus, on the fortified wall that extends across the isthmus, and daily filled up the trench with straw, the generals of the king set fire by night to the part thus bridged by day, and held out until they finally prevailed over them. And today everything is subject to whatever kings of the Bosporians the Romans choose to set up.

[7] Besides the places in the Chersonesus already enumerated, there are the fortresses Palacium, and Chabum, and Neapolis, ¹ which Scilurus and his sons constructed, from which they sallied out against the generals of Mithridates.

There was also a fortress called Eupatorium, built by Diophantus, one of the generals of Mithridates. ² There is a promontory, distant about 15 stadia from the wall of Chersonesus, which forms a large bay, which bends towards the city. Above this bay is a sea-lake, where there are salt pits. Here was the harbour Ctenus. The generals of the king, in order to strengthen their means of resistance in case of siege, stationed a garrison on the above-mentioned promontory, which was further protected by a fortification. The mouth of the Gulf was closed by an embankment which extended to the city, and was easily traversed on foot. The garrison and the city were thus united. The Scythians were afterwards easily repulsed. They attacked that part of the wall built across the isthmus which touches upon Ctenus, and filled the ditch with straw. The kind of bridge thus formed by day, was burnt at night by the king’s generals, who continued their resistance and defeated the enemy. At present the whole country is subject to whomsoever the Romans may appoint as king of the Bosporus.