She moved further along. Behind the stalls rose a twenty-foot-high wall of crushed cars topped with a line of remote guns and a satellite uplink array. A ten-foot-wide circular duct capped with ventilation grilles and a locked door projected from its center. A cheery neon sign read Unauthorized Entry Will Be Met With Lethal Force in bright pink. Beyond the wall, Alice spotted Pentagon habitation units, their interlocking cardboard walls forming recognizable offices, dining halls and training rooms. Above that, fading into the falling snow, were hints of glass and steel geometries.