Incidently, I am part of a project doing research on preindustrial trade in the 1st century AD.

Recently, we did some tests with reconstructed Roman barges. One or two men can haul them without problem, making about 1.8 knots upriver.

Historically, people were used more often than animals, it seems. Animals are much more enduring, in most cases (thats what the Austrian army teamsters told us, at least - we are also doing tests with mules to check what speeds beasts of burden were capable off and how far stuff could be transported per day).

Have you come across this: https://archive.org/details/soldierspocketbookfs1874 ?

It's from the 19th century, but the figures it lists for loads possible by mule, horse, ox, elephant etc. and miles per day (estimates for military planning) are pretty timeless.

Balesir wrote; Have you come across this: https://archive.org/details/soldierspocketbookfs1874 ?

Pages 39 to 45 is where to find that information. This book is an excellent source of information. Well done Balesir!

Jessee, I've been pondering your question since the initial post and would defer to other responders in terms of Terran historical comparisons.

However, I do want to point out that while the Region maps certainly show the four levels of roads in their keys (Paved, Unpaved, Rural Tracks, Wilderness Trails), only the first two show up enough at the Region scale to be considered nearly definitive. It's true many Rural Tracks, indeed, are also displayed in the Hurisea area (and elsewhere), but not necessarily all of them are—and certainly the few Wilderness Trails given are indubitably in the minority. The Atlas scale squares often depict more Rural Tracks and certainly more Wild. Trails.

I do think, however, that your conclusion about the lack of Rural Tracks parallel to the Tîrga likely implies no such "towing trail", but it's not technically disproven—and certainly not for isolated stretches. And it also depends on whether a case could be made for such towing trails being equivalent to Wilderness Trails. Not sure.

I'd like to hear from some of the KP map makers on this topic—I'll see if I can rouse them!

Well, you can always tow in shallow water - historically, this has been done and often might have been the default. I have seen pictures from the 18th century (if I recall correctly) which depict exactly that - often with animals, but sometimes with humans towing.