What therefore makes the situation of <a class="linkToPlace" target="_blank" href="/place?placename=Byzantium&groupId=415&placeId=767">Byzantium</a> so favourable and that of Calchedon the reverse is the fact here stated. To look at them indeed you would say they were equally well placed, but nevertheless it is not easy to reach Calchedon by sea, if one wishes, while to <a class="linkToPlace" target="_blank" href="/place?placename=Byzantium&groupId=415&placeId=767">Byzantium</a> the current carries one whether one wishes or not, as I just said.
Evidence of this is that those who wish to cross from Calchedon to <a class="linkToPlace" target="_blank" href="/place?placename=Byzantium&groupId=415&placeId=767">Byzantium</a> cannot sail in a straight course owing to the current between, but steer obliquely for the Cow and the place called <a class="linkToPlace" target="_blank" href="/place?placename=Chrysopolis&groupId=464&placeId=867">Chrysopolis</a> — which the Athenians once occupied by the advice of Alcibiades and used it when they first attempted to levy toll on vessels bound for the <a class="linkToPlace" target="_blank" href="/place?placename=Pontus&groupId=910&placeId=1634">Pontus</a> — and from hence commit themselves to the current which perforce carries them to <a class="linkToPlace" target="_blank" href="/place?placename=Byzantium&groupId=415&placeId=767">Byzantium</a>
The approaches by sea to <a class="linkToPlace" target="_blank" href="/place?placename=Byzantium&groupId=415&placeId=767">Byzantium</a> from the other side are equally favourable.
For those sailing with a south wind from the <a class="linkToPlace" target="_blank" href="/place?placename=Hellespont&groupId=620&placeId=1141">Hellespont</a>, or from the <a class="linkToPlace" target="_blank" href="/place?placename=Pontus&groupId=910&placeId=1634">Pontus</a> to the <a class="linkToPlace" target="_blank" href="/place?placename=Hellespont&groupId=620&placeId=1141">Hellespont</a> with the Etesian winds, find the course from <a class="linkToPlace" target="_blank" href="/place?placename=Byzantium&groupId=415&placeId=767">Byzantium</a> along the European coast to the commencement of the narrows at Sestus and <a class="linkToPlace" target="_blank" href="/place?placename=Abydus&groupId=268&placeId=523">Abydus</a> a straight and easy one, and so is the return voyage to <a class="linkToPlace" target="_blank" href="/place?placename=Byzantium&groupId=415&placeId=767">Byzantium</a>.
But the voyage from Calchedon along the Asiatic coast is the reverse of this, because one must follow the shores of a deep gulf, and the headland formed by the territory of Cyzicus runs out to a great distance.
Nor can ships sailing from the <a class="linkToPlace" target="_blank" href="/place?placename=Hellespont&groupId=620&placeId=1141">Hellespont</a> to Calchedon easily coast along Europe and then on approaching <a class="linkToPlace" target="_blank" href="/place?placename=Byzantium&groupId=415&placeId=767">Byzantium</a> turn and make for Calchedon, as the current and the circumstances mentioned above make it difficult.
And similarly it is quite impossible for a ship leaving Calchedon to make the coast of <a class="linkToPlace" target="_blank" href="/place?placename=Thrace&groupId=1030&placeId=509">Thrace</a> at once owing to the current between, and owing to the wind.
Both the south and north winds are adverse to both the attempts, since the south wind will carry one towards the <a class="linkToPlace" target="_blank" href="/place?placename=Pontus&groupId=910&placeId=1634">Pontus</a> and the north wind away from it, and these are the winds one must avail oneself of for the voyage from Calchedon to <a class="linkToPlace" target="_blank" href="/place?placename=Hellespont&groupId=620&placeId=1141">Hellespont</a> or for the voyage back.
Such are the causes of the favourable position of <a class="linkToPlace" target="_blank" href="/place?placename=Byzantium&groupId=415&placeId=767">Byzantium</a> as regards the sea; its disadvantages on the land side being as follows.
Walbank Commentary