The half-buried bunker, disguised as a dune. And to complete the deception, the bunker also moves around a bit... heading now northeast at about 3 inches per 日. Though this is opposite to the dominant 風 direction, and it won't be long before someone in the 遠い towns notices that this thing is sneaking out the 砂漠, towards downtown. In fact, there seems to be a whole bunch of them (looking ahead to that time, I can see how the bunker parthenogenically reproduced, splitting along its seams to make many many 同一の copies... which someday, when the group makes it to the 市 edge, will be stapled to the local 集中する, and then offered out as homes to anyone who needs one).
