New Zealand Archaeological Association Site Record Number Z17/233 is a pit site that forms part of the dense archaeological landscape of the Tolaga Bay (Uawa) area. It is located on Titirangi Station, to the southeast of the Tolaga Bay township.

Pit sites and the many other recorded archaeological sites including pa, midden, gardens and urupa reflect the intensive Maori occupation of the Tolaga Bay from the time of initial Polynesian settlement approximately 700 years ago. Access to abundant food resources from the sea, rivers, inland forests and horticultural production (kumara) meant that a large population could be sustained. It has been estimated that the early Maori population of Tolaga Bay totalled approximately 1200; and the main iwi was Te Aitanga a Hauiti.

Pit and pit/ terrace sites are very common in Tolaga Bay, and demonstrate the importance of horticulture to Tolaga Bay's earliest inhabitants. The Bay's fertile soils and temperate climate were well suited to kumara gardening, and the pits were used for storing harvested kumara over the winter months. Rectangular storage pits (which were once roofed with a layer of earth), are more prevalent than the underground storage pits found elsewhere in New Zealand, a pattern attributed to the harder substrate of the soil in this area. They are in fact the most common archaeological site type in Tolaga Bay, and are found along the river banks and on the rolling hills to the south of the Bay. They are generally located in clusters on knolls or terraces, or on ridge crests, in lines from end to end, as is the case with this site - Z17/233.

Pit site Z17/233 is located at the southern end of a remaining section of low ridge running parallel to the sea on the eastern boundary of Titirangi Station. It is in pasture, and is situated between the mouth of the Whakamarino Stream (to the south), and a tributary (to the north). One of the main farm roads leading through the station is located to the west of the site. Pit site Z17/234 is located directly north of Z17/233, on the opposite side of an eroded stream gully, and there are a number of other archaeological sites in the vicinity, including a pa (Z17/265) and several other pit and pit/terrace sites.

Z17/233 was first recorded by archaeologist Kevin Jones during his archaeological survey work in the Whangara, Tolaga Bay and Uawa Catchment areas in 1982-1983. This survey work was undertaken to gain information about the nature of prehistoric settlement in this locality, and also to evaluate specific sites for registration under the Historic Places Act 1980. Jones described the site as 'pits, drains and some artificial scarps on cliff edge' and completed a sketch plan, showing approximate measurements for some of the pits. The site was considered to be in good condition, but at risk of slumping in the future.

The site was revisited by archaeologist Vanessa Tanner in 2000, as part of the New Zealand Archaeological Association Site Recording Scheme Upgrade Project. Tanner concluded that the site was in average to poor condition, and under threat of continued stock erosion. A recommendation was also made that Z17/233 and Z17/234 be combined as one archaeological site, due to the fact that a recently eroded stream gully was all that separated them. A revised sketch plan of the site was completed. A 2007 New Zealand Historic Places Trust site visit to Z17/233 revealed no major changes to the site.

Z17/233 is one of numerous pit and pit/terrace sites recorded in the Tolaga Bay area, and it is part of a dense archaeological and cultural landscape that is of considerable significance to Te Aitanga a Hauiti. This landscape reflects the intensive Maori occupation and settlement of the Tolaga Bay area since the 14th - 15th centuries AD., and the important role that horticulture played in this.