+Thessaly [22.25,39.5] (region), Greece, Europe Thessaly, as tradition has it, was in old times a lake enclosed all round by high mountains. On its eastern side it is fenced in by the joining of the lower parts of the mountains +Pilion (mountain range), Nomos Magnisias, Thessaly, Greece, Europe Pelion and Ossa, to the north by +Olympus (mountain), Nomos Larisis, Thessaly, Greece, Europe Olympus, to the west by Pindus, towards the south and the southerly wind by Othrys. In the middle, then, of this ring of mountains, lies the vale of +Thessaly [22.25,39.5] (region), Greece, Europe Thessaly.

A number of rivers pour into this vale, the most notable of which are Peneus, Apidanus, Onochonus, Enipeus, Pamisus. These five, while they flow towards their meeting place from the mountains which surround +Thessaly [22.25,39.5] (region), Greece, Europe Thessaly, have their several names, until their waters all unite and issue into the sea by one narrow passage.

As soon as they are united, the name of the Peneus prevails, making the rest nameless. In ancient days, it is said, there was not yet this channel and outfall, but those rivers and the Boebean lake,In eastern +Thessaly [22.25,39.5] (region), Greece, Europe Thessaly, west of +Pilion (mountain range), Nomos Magnisias, Thessaly, Greece, Europe Pelion. Naturally, with the whole country inundated, the lake would have no independent existence. which was not yet named, had the same volume of water as now, and thereby turned all +Thessaly [22.25,39.5] (region), Greece, Europe Thessaly into a sea.

Now the Thessalians say that Poseidon made the passage by which the Peneus flows. This is reasonable, for whoever believes that Poseidon is the shaker of the earth and that rifts made by earthquakes are the work of that god will conclude, upon seeing that passage, that it is of Poseidon's making. It was manifest to me that it must have been an earthquake which forced the mountains apart.The correspondence in formation of the two sides of the pass (salients on one side answering to recesses on the other) gives the impression that they were once united and have been violently separated.