They’d disconnected the warning beeps: the mobile crane’s engine noise was bad enough to draw zombies from a couple miles in any direction. Fortunately after their sweeps there weren’t many of the walking dead still around, at least for now. Still, just in case, they kept pickets and lookouts posted.
The next timber was lowered slowly into place, sliding into the slit trench with ease. The ground crew unhooked the chains and began to lash it in place. In a week they’d have a fortress no horde could batter their way into: old school, frontier-style. Assuming they had a week.