The final mandatory piece of terrain that you need - are bunkers.
I considered making these from Green Stuff but whilst messing around with the scraps of self-adhesive foam left from trench production, I had an idea!
I cut a diamond shape and stuck it to a 40x15mm base.
Then I cut the "blockhouse" (a 6x4mm piece of foam) and stuck that in the middle if the diamond.
Then I cut an access trench to the rear of the blockhouse.
Finally I textured the base with Vallejo course grey pumice.
All that remained was to finish them off as described for the barbed wire.
I'm pleased with the finished result.
I've started work on some additional terrain pieces on 60x60mm mdf squares......more on that next time.