Royal Commission Appointed to Enquire into the Defence of British Possessions and Commerce Abroad 1879 to 1883 under the Earl of Carnarvon, designated Auckland as a Defended Commercial Port.
The principal coastal defence fortifications in Auckland were:
Fort Cautley or North Head includes a number batteries and defences works being the principal defence location.
Fort Takapuna was built in 1886 and mounted two 6-inch BL guns on HP mounts. Two 6-pdr Q.F. Nordenfelt were added about 1900.
Although developed over the years, most of the site is now open to the public.
Fort Victoria was built in 1877 with four 64-pdr RML guns. In 1885 the battery was re-sited and enhanced. In 1891 a fire control post was added with telephone communication to Forts Cautley and Takapuna.
In 1899 a 8-inch BL gun on HP mount was installed.
The battery can still be visited.
Fort Resolution was built in 1885, primarily of earth and timber. It mounted two 64-pdr RML guns. The site has now been lost.
Fort Bastion, built between 1886 and 1889 with two 6-inch BL guns on HP mounts. In 1889 two 6-pdr Q.F. guns were added for anti torpedo boat defence.
The site has been lost to development.
There is an excellent web site, NZ Coastal Defences, which covers well the Coastal Defences of New Zealand. They have original images and cover all the main locations. Recommended.