I've seen the air base and Port that are both floating with a moat around them. Air bases included the town on its own little island too. Last week, some clever young lads decided to up LVTs to take them. It was actually quite fun.
That being said, it does look like there's a hole in the map on my card and the bases/towns are phasing in and out of our dimension... but perhaps there could be a cool storyline behind this like 3rd Reich Scientists experimenting with time travel technology had a catastrophic failure during one of their high energy experiments causing the whole bases to shift out of our time continuum ala the Philadelphia Experiment or C&C Red Alert.
