Sniper Elite 3 Walkthrough: Halfaya Pass Part 1
Make your way through the trenches and past the gunners.
Take out the patrols and go past the windmill. Stay to the left and you will find a hidden path. follow it to the end and take out the talking guards after they finish their conversation.
Move through the buildings walls and stay left to find a hidden passage to the next area. there isn't anything here except enemies so kill them if you like, but to get to the next objective move through the small tunnel in the rock.
As you come out stay left and go up a small path to find a rooftop and a guard. Kill him and use this spot to take out the patrols and mask your shots with the burst of the artillery cannon.
Once the area is secure, move down to take out the men on the cannon. Go into the house and down the stairs. You will be directly under the men. Toss a grenade or use TNT + Tinder to set a timed charge.
After they go boom head to your next objective or look around for letters and rifle parts on bodies.