Fortifications, Obstacles and Cover
Many scenarios direct players to create the game board with a variety of fortification and obstacle elements. In addition, some fortification elements can be created during the game by certain unit types (such as engineer squads digging entrenchments), and some fortifications and obstacles can be created or removed by players using Operations cards provided to them by the scenario.
How horrible, how fantastic, how incredible it is that we should be digging trenches and trying on gas masks here because of a quarrel in a faraway country between people of whom we know nothing. (1938) 
