Book 2 of the downloadable manual has some information on that. There's a chapter on the map editor.
Four seasons.
Four weathers: Clear, Rain, Fog and Snow
"Several bridge models are available: stone bridges, wooden bridges, and pontoon
bridges"
Brook, lake, marsh, deep forest, forest, bridge, ford, town, village, castle, farm, hamlet, redoubt, camp, vineyard, plantation, road and lane.
Buildings have either western European or eastern European architecture. There are 3 styles of castles. There are 2 models of farms.
Hook