A big blob of concrete mixed with stones is all what remained from a simplified machine gun pillbox, one of many of this type built north of Niemirów on the Bug River.
They were cheap and simple to build and except from concrete and stones, collected on nearby fields, did not require sophisticated raw materials. They had no elaborate equipment installed and were supposed to support the mail line of defence which consisted of regular pillboxes that had been built closer to the river and further to the south.
This photo is Best on black at Fluidr
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