Justice, which handles inquiries for the Waitangi Tribunal, confirmed an agreement is progressing.
Neither party to the proposed deal was prepared to comment and publicity has been limited to a small story in a local newspaper, Hibiscus Coast Matters.
It is unkown whether public open days will figure in the final agreement.
At present civilian access to the historic land is restricted to infrequent visits, such as Orewa College history students and tours previously organised by Silverdale RSA.
Last week the Navy, which administers the land for the other Armed Services, allowed me in to conduct a photo shoot there for NZ Herald Driven.
I took a Cyclespot Ducati Multistrada to the 9.2 inch gun emplacements, the highest point of the Whangaparaoa Peninsula, hoping to use the spectacular views of the Gulf there as a brackdrop.
I spent my entire morning scrambling through underground fortifications which would do the likes of Dr Who or a Rings movie proud.
This Defence land, about a third size of the adjacent Shakespear Region Park, boasts dramatic cliffs, the most well preserved gun emplacements in Auckland, abundant native birdlife and remarkable artifacts.
Just outside the entrance to the remarkable 9.2 inch emplacements, a giant chain stretches mysteriously off into the bush.
It is part of a massive chain once designed to tether marine mines between Tiri and the Peninsula.
Each link looks to weigh well over 50 kg, while the length was originally said to be a staggering four kilometres.
Said to have once been several km long, used to tether marine mines and with giant links, this mysterious chain lies abandoned near the 9in battery at Whangaparaoa.
"The birds, which constantly swap between the island and the open sanctuary at Shakespear don't know where the boundary is between the Park and the Defence land, points of Friends of the Regional Parks chairman, and former ARC chairman, Bill Burrill.
"Because of this, pest eradication has carried on both on the Defence side and the Park side of the boundary. When it comes to our Regional Parks network, Shakespear is one of the jewels in the crown, as it's on a peninsula and therefore easier to protect from pests. The Defence land is part of that equation."
The land has two tunnel complexes dating from World War II.
The 6in battery is a dank ruin, though long tunnels, rooms and staircases leading to gun-emplacements on the north side of the Peninsula, are worth seeing.
A much larger, near pristine 9.2in battery site is the real star turn, boasting an incredible half-km of tunnels, rooms and staircases.
Used till recent years to store Naval ordnance, but now empty, this complex is in excellent condition, retaining its electricity reticulation and air supply.
Though used in the past as the set for reality TV shows, today nobody seems sure what to do with it.
The old 6in battery's tunnel complex is still used for training.
Secret weapon
A secret weapons programme was developed here more than 70 years ago.
Scientists at Whangaparaoa, and elsewhere, tested tsunami bombs, designed to overwhelm Japanese coastal defences. Later over-shadowed by the Manhattan Project, the development of this home-grown weapon of mass destruction remains a chilling story worth remembering.
Of course, the Training Area remains a live-firing-range, which is why so few civilians are allowed in.
Isolation behind big electronic gates is ideal for training various units, even the SAS. There's commando courses, cliffs and nicely regenerating bush.
On firing days, gunners practice with Steyr rifles and .50 cal machineguns and other weapons; boat skippers keep their distance when the "firing flag" is up.
Having built modern accommodation a few years ago, and with prospects of consenting similar firing range facilities near Auckland problematic, the military seem to value this site highly.
Surrounded by sea on three sides, and separated from its front gate by at least 1km of drive, it's near suburban Auckland, yet usefully isolated.
In 2001 the camp played host to 137 refugees transferred from the Mangere Refugee Centre to make way for asylum seekers from the Tampa.
But aside from usefulness in time of crisis, this land is an aesthetic treasure.
Naval artillerymen of old seemed to share common tastes with today's real estate tycoon, namely "views to die for".
The tunnels once shielded young soldiers willing to give their lives for Auckland.
A few dozen gunners underground could weather heavy sea bombardment and reply with their own cannon.
Those big radar-guided guns, now long gone, could have hit targets well over the horizon with pinpoint accuracy.
During part of the War, a rifle company, machinegun and mortar platoons, guarded the tunnel entrances from ground attack.
These defenders only ever got to shoot warning shots across the bows of civilian pleasure boats and merchant ships which strayed too near.
Poorly protected in puny pill boxes - if the Imperial Fleet really had sailed-up Auckland Harbour - their Lewis guns wouldn't have fired long.
Whangaparaoa Fortress is a monument to their bravery, plus tenaciousness of Public Works staff who hand-dug the tunnels, poured thousands of cubic metres of concrete, and ran power cables from Silverdale.
What they achieved on scant wartime resources remains a marvel.
