Surrounding country.--Whether generally open and passable for infantry, cavalry, and artillery, or whether broken and impassable, due to fences, woods, crops, ravines, etc.
Railroads.--Single or double track, narrow or broad gauge, tunnels, bridges, cuts, direction, stations, etc.
Bridges.--Material, wood, stone, steel, etc.: length and breadth; number and kind of piers or supports.
Rivers.--Direction; width, depth; kind of bottom, such as mud, sand, rocky, etc.: banks, steep or gentle, open or wooded; rapidity of current; variations in depth at different times as indicated by driftwood and high-water marks; islands; heights in vicinity commanding streams.
Woods.--Extent and shape; kind of trees; free from underbrush or not; clearings, roads, swamps, ravines, etc.
Telegraph lines.--Number of wires, along ronds or railroads, stations, etc.
Villages.--Size, kind of houses, nature of streets, means of defense, etc.
Hills and ridges.--Whether slopes are gentle or steep; whether top is narrow or wide; whether ground is broken or smooth, wooded or clear; whether difficult or easy to cross, etc.; whether commanded by other hills.
Defiles.--Their direction, length, and width; whether surrounding heights are passable for infantry and artillery; kind of country at each opening of the defile, etc.
Ravines, ditches, etc.--Width and depth; banks, whether passable for infantry, cavalry, and wagons; whether suitable for trenches, or for movement of troops therein, etc.