My story building is partially affected by High School History teacher who was convinced that geography affected history. I tended to like this concept.
All of my stories start as maps. My knowledge of geography is rudimentary...
Mountains follow faults, which may/may not be near a continental shelf...some distance from shoreline. Too many mountains produce desert on the opposite side do to the rain shadow effect. There is more percipitation at higher altitudes which lead to the formation of rivers. Where water pools, lakes can be found. Trees follow water. Rivers dump into ocean.
And natural barriers (mountains, rivers and forests) produce national boundaries.