Suppose you have range of mountains down the middle of a country, with a prevailing wind blowing off an ocean. As the wind hits the mountain slopes it is forced upward, cooling the air and making it less capable of transporting moisture, which it disposes of onto the ground below. That's where you build your Manchester (or Seattle). Higher up, the moisture comes out as snow, building your glaciers and the foundation for your river system.
But now it swoops down the other side, warming up; now it could carry more moisture, if it had any left to carry. A dry wind; if the mountains are high enough, and the wind direction reliable enough, a desert (see the Atacama; desiccated on the edge of the world's biggest body of water). A hydraulic shadow of the peaks, almost as sharp edged as a light shadow, one whole face getting no precipitation.
How high are your mountains? Are they young, enthusiastic mountains like the Himalayas, or older, timeworn, smoothed lumps like the Grampians or the Jura? Mainly forested, or essentially rock and scree? It all changes the problems of getting across them, even without someone who's reluctant to make the journey. So, as well as having your contour chart you have to visualise the surface, how deep the passes are cut, whether a particular valley channelises the wind into your face, or back…
Even if you don't say a word about this to your readers.