Survival bread, also known as hard tack, pilot bread, ship biscuit or sea bread, was used throughout history during wars, on long sea voyages and in other survival situations where an inexpensive food was needed that would keep indefinitely. Survival bread is still baked and eaten today by survivalists, hikers and campers who need a long-lasting food source that doesn't require refrigeration. Survival bread contains stable, non-perishable ingredients, and lasts for a year or longer when stored in an airtight container.
Turn on the oven and preheat it to 400 degrees.
Add flour and a generous pinch of salt to a mixing bowl; you need 4 cups of flour to make 2 pounds of survival bread. Mix the salt and flour together with a spoon.
Add water to the flour and salt mixture, a little at a time, while you mix it by hand. The mixture should stick together but not to your hands or the rolling pin. The idea is to use as little water as possible to achieve this.
Roll out the dough with the rolling pin, shaping it into a large rectangle, until it's about 1/2 inch thick.
Cut the dough with the knife, creating 3-by-3-inch squares. Poke each square with a wooden skewer without punching completely through the dough, making a 4-by-4 pattern of holes. Repeat this hole pattern on the other side as well. The holes will enable you to break the bread easier once it's cooked.
Put the bread dough on a dry cookie sheet and place it in the oven. Bake the dough until lightly browned on the edges, about 20 to 25 minutes.
Wait until the bread is completely dry before removing it from the oven. Store the survival bread in a closed container away from moisture.