Check out this website with lots of photos and info on “secret” military bases; http://www.secret-bases.co.uk/secret4.htm
Write a story or create a scenario set in or around one of these places. Imagine if backpackers or a tourist bus stumbled upon one of these places, not realising what it was. What if they tried staying the night in the FIBUA town? What if the bases were being used for sinister government experiments and an unsuspecting combi-van full of vacationing students was exactly what they needed…