Constructing the Fortress

While looking through the "Endgame Articles" section, I noticed that there were no articles on the topic of fortresses. As I a fan of using fortresses, and they are relatively unheard of, I decided to write an article explaining them. A fortress is a defensive formation or position set up by the player with less material to achieve a draw. They are an excellent method of bringing about a swindle, and seeing the crushed look on your opponent's face when the game is drawn is priceless. The simplest fortress is used with a king versus a king, rook pawn, and bishop. Note that this only works if the bishop's color is the opposite of that of the pawn's queening square:

In this position, the white king merely shuffles back and forth between a1 and b2. The black king is unable to reach the corner, and the bishop, being on the wrong color, cannot check the white king. Therefore the black pawn will be unable to successfully promote, and the game will be drawn.

Another common fortress is played with a king and bishop against a king and rook. It is built by placing your king in the corner, with your bishop next to it:

The king rests in a corner whose color is the opposite of the bishop's. Once again, no matter how hard white tries, they will not be able to beat black because the bishop, shuffling along the a2-g8 diagonal, can always return to g8 and defend the king.

The third and last fortress of which I know is assembled with a king, knight, and bishop, and defends from a king and queen:

In this fortress, the king waits in a corner, behind the bishop, with the knight defended by the bishop. Since all of the pieces defend each other, neither the king nor the queen can take any of them. The king, knight, and bishop control a 3x3 square in the corner, which prevents the enemy king from getting close enough to assist in a checkmate.