@ Falconius

That's pretty much what I was thinking. The majority of the civilization will be reliant on The River (as apt a name as any). Those living further from the banks less so, though it would still remain the major form of long distance transport.

I understand your point about ferry routes being shown as they are integral to transport and considering that I am showing roads I should probably include said ferry routes. My main concern is that as things are now The River has a width of 4-5 pixels (2-2.5 km). This doesn't really leave much room for the depiction of ferry routes. I seem to have the option to either increase the resolution of my map (already 5200x2800) or leave out river traffic routes and only include them in zoomed maps for particular areas (capitals and what-not).