When Xerxes saw from +Thessaloniki [22.933,40.633] (inhabited place), Thessaloniki, Macedonia, Greece, Europe Therma the very great height of the Thessalian mountains +Olympus (mountain), Nomos Larisis, Thessaly, Greece, Europe Olympus and Ossa and learned that the Peneus flows through them in a narrow pass, which was the way that led into +Thessaly [22.25,39.5] (region), Greece, Europe Thessaly, he desired to view the mouth of the Peneus because he intended to march by the upper road through the highland people of Macedonia (region (general)), EuropeMacedonia to the country of the Perrhaebi and the town of Gonnus;Xerxes' army might have entered +Thessaly [22.25,39.5] (region), Greece, Europe Thessaly by marching along the coast between +Olympus (mountain), Nomos Larisis, Thessaly, Greece, Europe Olympus and the sea, and up the Peneus valley (the pass of Tempe) to Gonnus. Instead, it crossed the mountains; probably both by a route which runs across the southern slope of +Olympus (mountain), Nomos Larisis, Thessaly, Greece, Europe Olympus to Gonnus, and also by the +Petra [35.433,30.333] (deserted settlement), Maan, Jordan, Asia Petra pass, further inland, between +Olympus (mountain), Nomos Larisis, Thessaly, Greece, Europe Olympus and Bermius. But Herodotus is mistaken in making the a)/nw o(do/s alone reach Gonnus; the Tempe route would have done the same. this, it was told him, was the safest way.

He did exactly as he desired. He embarked on a Sidonian ship which he always used when he had some such business in hand, and hoisted his signal for the rest also to put out to sea, leaving his land army where it was. Great wonder took him when he came and viewed the mouth of the Peneus, and calling his guides, he asked them if it were possible to turn the river from its course and lead it into the sea by another way.