The Histories · 7.128

Then Xerxes seeing from Therma the mountains of Thessaly, Olympos and Ossa, that they were of very great height, and being informed that in the midst between them there was a narrow channel, through which flows the Peneios, and hearing also that by this way there was a good road leading to Thessaly, formed a desire to sail thither and look at the outlet of the Peneios, because he was meaning to march by the upper road, through the land of the Macedonians who dwell inland, until he came to the Perraibians, passing by the city of Gonnos; for by this way he was informed that it was safest to go. And having formed this desire, so also he proceeded to do; that is, he embarked in a Sidonian ship, the same in which he used always to embark when he wished to do anything of this kind, and he displayed a signal for the others to put out to sea also, leaving there the land-army. Then when Xerxes…

Herodotus of Halicarnassus · trans. G. C. Macaulay, 1890
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