# [RPG] Middle age transportation by river questions

campaign-developmenttravel

I am playing in a medieval fantasy type setting and am trying to determine travel speeds when people are traveling on rivers. This is similar to this previous question, but that question really only covered ground-based travel speeds. Assuming normal medieval/early Renaissance type methods of travel, and putting aside the question of magical augmentation,

• How fast can a sailboat travel downriver with a tailwind?
• How fast can a sailboat travel upriver with a tailwind?
• How fast can a sailboat travel downriver with a headwind?
• How fast can a sailboat travel upriver with a headwind?
• Were there other commonly used forms of travel by river?
• Did boats typically dock for the night?

Thanks for any help!

According to this source, the speed of a sailing boat depended on the waterline length.

The exact formula quoted there is `hull speed = 1.34 * sqrt(waterline length)`

A boat with a waterline length of 50 feet would therefore go about 9.34 knots (~17.3 km/h or ~10.75 mph). This of course only applies on open sea with good wind.

I have not found any sources for the maximum speed on a river, but I guess it's safe to say that it would be half the speed, at best.

Those guys discussed something similar, and came up with an average travelling speed of 5 knots (~9.26 km/h or ~5.75 mph) for a trading ship with a waterline length of 75 feet. That would, of course, change depending on wind conditions, the river (Does it run straight or in a lot of turns?) and your direction on the river (Upriver, downriver). But I have no Idea how the exact modifiers are for this.

As for the rest of your questions, I have no idea and hope that someone else here can help you. Take this as a general direction, not a fully fleshed out answer. ;-)