Originally during the daily roll call, thee entire prison population had to stand at attention in this square. As new buildings were constructed, they were then lined up in front of the blocks. Roll call often lasted several hours and on occasion 12 hours. The purpose was to count the prisoners and assess changes fro new arrivals, deaths, transfers to other camps, "releases", and escapes. Prisoners had to stand at attention the entire time and could not leave for any reason.. When the exhausted or sick fell over, functionaries beat them to force them stand up again. Inclement weather - pouring rain, freezing, or high temperatures contributed to many death. the dead were laid out in rows next to the living and afterwards taken to the morgue and crossed off the list. During some roll calls the exhausted or sick were selected for death in the gas chambers, executed by hanging, or publicly flogged. Mobile gallows were used during roll call for hanging those who had been caught while escaping, those suspected of preparing to escape, or those who helped fugitives. On July 19, 1943, the largest public execution of 12 of the surveying squad occurred with these specially built gallows in retaliation for the escape of 2 of their group and for contact with civilians. After the war, the gallows were reconstructed.