How far can a ship travel in one day?

[Ghostman]

Professor emeritus Lionel Casson discusses this topic in the context of Mediterranean sailing during the classical antiquity in his book Ships and Seamanship in the Ancient World. He estimates that most sailing ships of the time made an average speed of 4-6 knots under favourable wind over open waters, and less than 2-2½ knots sailing against the wind. (p. 288, 291) The actual speed for any particular voyage during that era could be significantly faster or slower than these average figures, though. This also consides only the typical speeds of individual ships, which as professor Casson notes, cannot be taken as an indication for the speed of a fleet of ships. A fleet only travels as fast as it's slowest element. For fleets he provides the estimate of 2-3 knots under favourable wind, and no better than 1-1½ knots under light or unfavourable winds. (p. 296)

[Peter 67]

It's also just dealing with a relatively shallow sea with completely different dynamics to ocean travel, the ships that sailed accross the Med became costal huggers out in the Atlantic ocean. The realative ease in sailing in the Meds the reason that so many sailing nations grew up there, even transporting their experience of the Med to the narrow English Channel caused the Roman Navy a major headache. Plus most of the ships of that time relied heavily on oars rather than sails for their mo t ive power.