Historic air defense bunker

This bunker was built in 1943. It was bombed in 1944 but it withstood all bombs. With three floors it could shelter a total of 2200 employees from the nearby factories. It had reinforced concrete walls with a thickness of 50 cm reinforced with 1,8 cm rebars. The local authorities had already tried to demolish it in the early 2000s but the available technology proved insufficient. Recently they started to demolish the building with two hydraulic breakers but it seems it's gonna take a long time to finish the job.