I was going to ask what kind of terrain was going to be between the two rivers, but your planning sketch answers that. I'd expect that the rivers would act as a moat--the older parts of the city would be there, with light walls along the riverbanks and stronger fortifications on the eastern part of the map. Bridges would probably also be fortified, and there might be forts further upriver to control ford points. You'd not see those on this map, of course, but you'd see the roads. There would also probably be a good deal of farmland between the rivers, where it would be better protected from an invader.