Trenches Quickquiz 1. Front line trenches were four feet deep. 2. Soldiers in the front line trenches were often killed by stray bullets. 3. First aid stations could be found in the support trenches. 4. Machine guns were located behind the front line trench. 5. Sand bags gave good protection from shells. 6. Soldiers stood under the fire step to shoot. 7. Bolt holes were built into the walls of the trenches. 8. The sump was a drainage channel. 9. Many soldiers suffered from trench foot. 10. Trench foot could be avoided by using whale oil.