I had chosen a area where it had been a German camp during the war, some 300 soldiers had been stationed here, guarding a nearby POW camp and overseeing the work on the railroad. Someone had told me about some concrete constructions in the forested hillside above the camp area and I had to investigate it.
Crossing the field I had a good signal and had to see what it was. I drew the shovel into the ground but it was like hitting asphalt. 3-4 days of subzero temperatures had frozen the ground completely. Luckily the top 5-10 cm was no match for the axe and I could get to the rust. Ofcourse it was some agricultural rubbish.
In the hillside I found a small plateau with some concrete stuff. From what I could see I think it was some kind of communication mast. I dug a few signals here and found pipes and wires mostly but will certainly do some more searching here come spring.