Tomoana Pā (T12/1) is one of the first sites recorded in the Whangamatā area by Roger Green and is a prime example of an extensive defended hilltop pā. Its current extent is around 11,450 m² and it is approximately 270 m in length (north–south) along a ridge, and at least 50 m wide. Two terraces were investigated in March 2020.
After topsoil stripping, the site proved to be relatively complex with intercutting features and multiple phases of occupation in both areas investigated. At least 20 pit storage features were present which were not identified on the surface.
The small upper terrace just below the tihi appeared to solely have been used for cooking. Intercutting features here indicate a period of continued use. Three occupation phases were recorded on the lower, south facing terrace, indicating separate uses for the same area over time. The earliest phase is a series of crop storage pits most likely used for kūmara. Their intercutting nature indicates multiple episodes of re-use within this occupation phase. Three fire features are cut into the base of the largest storage pit and may represent a way of drying or disinfecting the interior between uses, however given shell was present in one of the features, it is more likely these represent a sheltered place to cook and therefore a secondary use of the feature.
The storage features appear to have been deliberately infilled with a homogenous clean fill and this surface then used for an unspecified occupation which involved some cooking features and several alignments of postholes. It is possible the alignments represent fences or windbreaks to compensate for the exposed nature of the terrace. These posthole features are filled with midden from what appears to be a later cooking phase which had been partly destroyed by modern damage to the site, with the remainder redeposited down the slopes.
While investigations of T12/1 were restricted to two terraces, gardening would have been carried out in the nearby vicinity and the tephra soils around the lower slopes of the hills would have been ideal for kūmara cultivation as they are well drained and friable and would have warmed up rapidly in the spring. The amount of storage pits alone indicate that gardening and crop storage was important, as was collecting and eating shellfish. This site is also an example of how modern modification of the landscape through an access track establishment (bulldozing) and forestry activity can obscure sites, but not destroy them. Further, it is likely that compaction caused by heavy machinery operating on the lower terrace aided in the preservation of the archaeological features below.