A trench or shelter were 5ft deep, 6ft wide and long enough to accommodate the number of people allocated to each. It was covered with corrugated iron, on which sandbags and clay were heaped. The air and light came in through unglazed openings at the top of the sides. It were used to take cover from enemy fire or the brave could shoot from it on the enemy.
The Sister's trench.
The trench prepared for the Sisters was in the Hospital grounds, adjoined to the Convent. It was 50 ft long and connected with the convent by an open trench, deep enough to conceal a person walking upright.
Below: The trench between the Convent and Hospital