patchbunny
Graduate Poster
I am not quite sure how to translate "Abfahren" - it is a little ambiguous. "Drahtspulen" is "wire bobbins" or "wire rolls" at any rate. "Abfahren" could mean that someone drives along them (for an inspection?), or that they are unspun.
I would say "Unspinning of wire spindles"
Apparently, they are heavy and need 4 hourses drawn together to be unspun.
I wonder what that row of little crater is at the top left.
Most likely they are deploying communication wires, possibly to the front lines or between command posts.