How did Medieval European river passenger transport develop?

Question

I read some sources that transport by boat over European rivers developed already in the early medieval period, ie after having developed ships with low draft as well as the invention of a controllable rudder. However, boats were mostly used for transport of goods. Transport of passengers developed much later, ie late medieval period (1350-1500), despite there being many travelers, such as merchants and pilgrims.

1. Why did passenger transport over water take off so much later? Was it because the passenger numbers were too low to make it profitable?
2. In case of combined goods and passengers service, were passengers convenienced in any way, such as benches to sit on, awnings against sun/rain?
3. The upstream trip would presumably require the use of a sail? Would that mean that the height of masts were such that the boats could sail under bridges? If not, what would be a common mode of propulsion?

Here are a few images that show various ship types from the late medieval period, albeit none specifically for people transport, other than a row boat: shipno1, shipno2, shipno3, shipno4, shipno5, shipno6

Then there is the Ulmer Schachtel, as used in Bavaria (Danube), but designed for goods transport, not specifically people. It states "Ships from Bavaria did also sail upstream to Ulm, but the people of Ulm had no ships of their own at that point." and "done by raft".

Also this source mostly discusses goods transport and makes the point that "most inland Utrecht-type ships must have been towed, poled, or oared."

Answer 1

River transport was used very much already in the Neolithic and Ancient times. Fast, cheap, quite reliable. It was used both for goods and travelers.

1. What developed in late Middle Ages was a trans-european waterway transport service economy. This is only true for northern Europe. Southern Europe does not have many navigable rivers, plus, its navigation economy was tied in the Mediterranean sea, and the "Mediterranean transport service economy" was never out of business even after the fall of the Roman Empire.
2. I'm not an expert on this but conveniences were poor. Just sit in the barrel, Joe.
3. No sails for river navigation. That's a crazy idea that would get you crushed against the river edges pretty quickly. Just rowing was used.

Answer 2

Upstream the boats were usually towed by men or animals on the river bank. In Russia, people in this trade were (later?) known as Burlaks, but similar jobs existed in other countries too, notably on the rivers in Germany.

Punting was quite common on short river sections where towing was not possible.