There's the Armstrong Disappearing Gun at Taiaroa Head, in Dunedin, and similarly historic guns at the Green Hill Fort on Thursday Island.
The guns were installed after several "Russian scares".
These began around the time of the Crimean War (1854-56) but it wasn't until a scare in the 1880s, when Britain and Russia were at loggerheads over Afghanistan, and Russian warships were making visits to Sydney, Hobart and Auckland, that Australia and New Zealand seriously began building strategic defences against the possibility that the Russians might invade.
The Dunedin gun was in place by the end of the decade and the Thursday Island ones soon after.
We had the opportunity to visit the guns at Green Hill Fort on Thursday Island during our trip to the top of Cape York, the most northern point on mainland Australia.
After we had been to "The Tip", we went on a Thursday Island tour, which included the 75-minute ferry ride and a two-hour visit.
The island tour included a general look at this tropical 3.4sq km island with its historic churches and public buildings, and a visit to the Japanese section of the cemetery where many pearl-divers are buried.
The highlight, however, was a visit to Green Hill Fort and the Torres Strait Historical Society's museum.
The fort was armed with three six-inch breech-loading guns and we spent quite some time walking around the top of the perimeter wall looking at these guns and the fort in general, while enjoying views down to the town, parts of the island and out to sea.
The museum has excellent displays, not only about the fort's original purpose, but its role in World War 1 and World War 2, as well as the pearling industry.
It was here we learned that the Green Hill Fort guns were only (allegedly) fired once in anger when, during World War 1, a ship steaming through Torres Strait failed to identify itself.
After a shot was fired over its bow, the ship quickly identified itself as friendly.
We thoroughly enjoyed the visit to the fort and finding out it has links with Dunedin, all because both Australia and New Zealand got the jitters over the threat of a Russian invasion.
• Sara Keen lives at Lake Hawea.
