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][1], 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!

  [1]: https://rpg.stackexchange.com/questions/1359/good-resources-for-travel-times%20this%20question