ENGLISH - Euripus Strait - From Wikipedia

The current consensus is that the Euripus was closed by a dike of coarse sediment until about 6000 years ago.^[3] It was opened following an (unrecorded) earthquake and remained open (see Herodotus, e.a. VII.173 and VIII.66, on the sea-battle of Artemision) until 411 BC, when the Euboeans decided to renounce their status as an island subject to Athenian hegemony and make themselves part of Boeotia (Diodorus Siculus, Bibliotheca Historica, 13.47, sections 1–8). There is no trace of this either in Thucydides or in Xenophon (in History of the Peloponnesian War and in Hellenica respectively.) Diodorus mentions specifically that gaps had to be left in the dike to allow the Euripus tides to flow through and that the current became much more intense owing to the narrowness of the passage and says that a single passage was left just wide enough for a single ship. Strabo (IX.2.2) wrote of some later time when there was a bridge two plethra long (approximately 50 m, which is probably an exaggeration). Some vestiges of the two ends of the dike of 411 probably remained, so that this later bridge was probably narrower than the channel that existed before 411 BC. We have no information about the depth, but even in the case of a channel about 50 m wide under Strabo's bridge, the depth could have been scoured out to a level entirely sufficient for ancient shipping.

It is not until the time of the Emperor Justinian I, that we have evidence of two channels in the Euripus, the large original channel and a new, narrow cleft to the east of it, so narrow that it could be crossed on a plank of wood. (Procopius, On the Buildings, 4.3.16.) This later stream is what was eventually widened to make the present shipping channel. At the time when Procopius wrote, the name of the fortress on the Euripus was probably "Euripus," which had become "Egripos" by 1204, and was adopted and slightly altered to "Nigriponte" by the Latins who occupied the place in 1205. (The name has nothing to do with any sort of "Black Bridge," except as a Veronese or Venetian joke, or folk-etymological corruption or re-interpretation in reference to the old bridge across the channel.)

In 1395, Nicola di Martoni came to Negropont during the return from his pilgrimage to Egypt and Palestine.^[4] He is clear that the main shipping channel in the Venetian period was on the side of the Boeotian mainland, and mentions the mills on the narrower channel, which he says were sometimes broken in the speed and turbulence of the flow there.

We have further information about the shipping channel and its single wooden bridge from various documents in the archives of the Venetian Empire. In 1408, the formation of a reef under the bridge severely affected shipping (http://www.archiviodistatovenezia.it/divenire/collezioni.htm Senato, Deliberazioni, Misti. 48,43v) and in 1439 there was concern over the tendency of the current to erode the surroundings of the pilings that supported the bridge (http://www.archiviodistatovenezia.it/divenire/collezioni.htm Senato, Deliberazioni, Misti. 60,140r–42r).^[5]

Evliya Çelebi, in his Travel Journal (SN VIII250a27, ff.), tells us that the narrow channel was first opened out enough for a galley to pass through at some time in the late 16th century, and was still just barely wide enough at the time of his visit in 1668 for a galley to squeeze through, even though the old shipping channel had been abandoned. By the end of the 18th century it was well on its way to being the width of the modern channel.

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