A small thing, but interesting as there seems comparatively little war infrastructure remaining in NZ (?) The store, but no explosives. Part of the preparations for a Japanese invasion: http://www.stuff.co.nz/auckland/local-news/eastern-courier/2333933/WWII-relic-hidden-safely-in-reserve ~A
Strangely enough - NZ seems to be quite a home for Home Guard history and memorabilia of various types, looking around the Net it seemed far better developed there than in Oz. That nifty repro "Home Guard Manual" that Tempus Press printed a couple of years back, for example - was a reprint of an NZ item.
There's still quite a bit of the old stuff left -- it's just well camouflaged. Tank traps were built using old truck tyres filled with pipe and concrete. Other traps were built using whatever material was available. Today, a lot of the old pillboxes are buried in the dirt, with just the top of the box outlined in the dirt. A couple weeks ago I discovered an old barracks near Castor Bay walled up behind a garage dug into the rock. During the height of the war, the best job of camouflage was the gun battery at Castor Bay which was made up to look like a beachfront holiday camp, complete with bungaloes (BL 6-in MK VII on PIII mounts), a tennis court (painted concrete cover on 84,000L water tank) and an ice cream parlour (battery observation post). The Japanese pilot who flew over Auckland before the AA batteries were set up reported seeing the emplacements at Whangaparoa, Motutapu and Takapuna/North Head but missed everything else.