u/BakerdaBeast

I started a game playing the Inca in exploration after doing one with Songhai, and I admit, I got tripped up by the fact their ability to do this with navigable rivers is very similar except the Inca's requires that the tiles be worked, and that the settlement is a city. Is there an actual reason for this? Working the mountain tiles kind of makes sense seeing as that is something the Inca can do and are themed around, but the city requirement feels random and doesn't really synergize or anything?