Concealed in the bush just outside Mallacoota, this RAAF military bunker makes for a somewhat surreal visit. A high-security communication installation during WWII, the bunker is now a museum and details its history through various displays. Even if you're not here during the limited opening hours, it's worth coming down for a look from the outside, as there are exterior information panels.
Inside there's interesting background on the Japanese submarines that patrolled this eastern coastline, sinking 22 Allied ships and claiming 194 lives.