I think an opportunity was missed when this question was asked, but closed.

It is relevant to worldbuilding in the same way that this question and this question are, to determine how far apart specific locations such as land masses, islands, etc. should be placed from each other, or how large a particular large body of water should be to provide a particular level of separation between two places involved in the story. Or for deciding on a technology level for ship-building in a fictional society when using a predetermined geography, it is useful to know travel times and distances for different ship types and technologies from different time periods.

How far could ancient, medieval, and otherwise pre-modern, ships travel in a month?

Best answers will include information about both rowed (when applicable to the time-period) and sailing ships from a respectable variety of civilizations/groups/time-periods (e.g. viking era, ancient greek, ancient rome, middle-ages, etc.).

To avoid over-complication, limit ship types to the largest 'standard' ships that would have been in common use for any time-period time for cargo, passenger travel, or war. And approximate distance ranges should be used, to account for variations among individual ship specimens, as opposed to specific distances of a single type in use in a particular time.

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    $\begingroup$ Why is this worldbuilding and not just asking about a real life historical fact? $\endgroup$ Jan 17, 2019 at 17:16
  • $\begingroup$ @Bellerophon Like the horse speed question I referenced, ship speeds and travel times can determine how far apart land masses, islands, etc. should be placed from each other, or how large bodies of water should be, to achieve a desired travel requirement for a story or plot point. Especially in Gaming applications of worldbuilding, this is especially useful for map creation. $\endgroup$
    – Harthag
    Jan 17, 2019 at 17:56
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    $\begingroup$ @elemtilas Something's wrong with that link. It takes me to a home page of a website (apparently belonging to a random individual) and I can find no indication of anything relevant on that page. Can you please explain, or correct the link? $\endgroup$
    – Harthag
    Jan 17, 2019 at 19:15
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    $\begingroup$ @Dalila, from our help center: avoid asking subjective questions where ... there is no actual problem to be solved and You should only ask ... questions based on actual problems that you face. The downvote mouse-over states, This question does not show any research effort.... This was closed because it's a basic research question that doesn't solve an actual worldbuilding question that you have. It is not the purpose of this site to simply be an aggregator of information located elsewhere. $\endgroup$
    – JBH
    Jan 17, 2019 at 20:26
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    $\begingroup$ All the links work fine for --- dunno what the issue is at your end. You'll have to manually look for "Speed Under Sail of Ancient Ships" by Casson. $\endgroup$
    – elemtilas
    Jan 18, 2019 at 0:38

1 Answer 1



Ancient ships: less than 1,000 km per month, potentially, assuming good weather, shoreline hugging, known waters, and a pressing need to do so.

More likely is 250 km per week, especially assuming some serious R&R at the end of that week, to include time for planning and time to let weather blow over, etc.


Here are some notes I made some years ago when trying to figure out ancient ship speeds. The ships I was interested in were all pretty much galleys -- ships that were typically rowed, but had a primitive square sail that could be used when the wind was going your way.

The other major factor was that a galley was designed more or less for day-travel only: it typically hugged the shoreline, and carried a day's worth of water, thus you had maybe 6 to 8 hours of travel time before having to knock off for the day and sleep on the shore.

With all those caveats, I drew numbers from a book on ancient ships that for the life of me I cannot remember the name of. It seems that longships, triakonters, liburna, biremes and triremes had roughly similar speeds. The pentekonter may have been a bit faster. To wit:

7kph rowing average, and perhaps 8 to 9 kph for pentekonters, maybe. Double that if the wind was favorable, and for very short rowing bursts. Double THAT if the wind was ideal, which I assume is rare to nonexistent.

Assume, then, that that's 50 km per day. In a week, a galley could therefore cover as much as 350 km. Although I bet actual weekly distances would be a standard deviation shorter (250 km).

Therefore, in a month, I'd say no more than 1,000 km -- and probably less, since I doubt the ships and rowers were built to operate 30 days straight with no downtime. But your ship, if keeping to shorelines with known characteristics, could cruise around for several hundred km in a month if pressed to it.


For a rule of thumb, realistic speed is roughly the same as marching speed. 2-5 knots. Occasionally faster under full steam with the wind at your back, even up to 15 knots, but not consistently.

Ship ratio appears to be a good metric for predicting speed as well as carrying capacity, by the way: Larger ratio = faster ship, Smaller ratio = more payload. Ship size also apparently affects speed. And of course, skill also affects speed.

Galley Era: 3000 BC to AD 1500, approximate

  • Galleys: "Vessels larger than boats, propelled primarily by oar power and only occasionally by sail."
  • Coast huggers.
  • Light. Operates in shallow waters, rivers, small bays.
  • Can be dragged on short overland routes.
  • Navigation by the sun, prevailing wind, and stars.
  • Stored in "ship sheds" on the shore.
  • Ships are transports. Wooden platforms for melee combat.
  • One (or more) rowers per oar.

Design Considerations

  • Length implies => number of oars per side (1 per 1.5m?)
  • Up to 3 levels of oars per side; more levels = more upkeep, lower endurance (3 levels = typically just a day's worth of fresh water)
  • Can have multiple rowers per hull
  • Catamaran hull doubles the hull size, increases carrying capacity more.
  • Maximum rowing speed is 2x average rowing speed?
  • Speed under sail is 4x average rowing speed?
  • Some ships have a ram...

Ships Light, fast, Scout/Raiding/Pirate vessels: Longships in general

  • 6 to 34 benches (on a side?)

Longship & Triakonter

  • 24m x 5m
  • 16 oars per side, 32 rowers total.
  • Crew of 40, maximum capacity 70.
  • 28 kph under sail max
  • 14 kph rowing max


  • 38m x 4.5m
  • 25 oars per side, 50 rowers total.
  • ?? kph under sail max
  • 18 kph rowing max?

Bireme or Liburna

  • 33m (or more) x 5m
  • 18 oars (or more) per side, 2 levels of rowers, 1 rower per oar.
  • 28 kph under sail max
  • 14 kph rowing max.
  • 7 kph rowing avg.


  • 3 levels of oars, 85 oars per side, 1 man per oar.
  • 14 kph rowing max. 7 kph avg.
  • Good offensive strength. Ram.
  • Only carries one day's worth of supplies (i.e. fresh water).
  • Lots of upkeep.
  • Tactically inferior to Liburna.
  • 24m to 37m or more. 3m to 5m wide.
  • $\begingroup$ What is "ship ratio"? $\endgroup$ Jan 17, 2019 at 17:57
  • $\begingroup$ I think it's the length-to-width ratio. Longer ships are faster because they can fit more rowers for the same surface area. But they can't carry as much stuff because more rowers means less available space. $\endgroup$
    – Ryan_L
    Jan 17, 2019 at 18:43
  • $\begingroup$ Thank you for the original answer, it fit relatively well with the original format of the question. However, The question, as originally worded, apparently didn't meet site guidelines, and has been significantly altered since your answer was posted. You might want to read through the updated question and adjust your answer and format accordingly. $\endgroup$
    – Harthag
    Jan 18, 2019 at 13:52

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