We reached building E with no further incident. Like all the other buildings on the ISP site, it had neither windows nor lights. It also showed the "concrete blockhouse" style of architecture of all the structures we'd seen during our guided tour. The ferroconcrete-composite walls were angled at almost forty-five degrees, and the corners were slightly rounded to offer no salients. It was almost as if the architects had designed with defense in mind. I was sure those walls could withstand a couple of shots from a panzer's main gun.