Te Pokohiwi o Kupe | Wairau Bar in the Marlborough region is where one of Aotearoa New Zealand’s earliest archaeological heritage sites is located, dating back to the early 1300s. This article describes a baseline study to map the effects of present-day and future sea levels on archaeological heritage land at Te Pokohiwi ō Kupe. Results suggest that approximately 20% of the heritage land is susceptible to a 100-year storm-wave inundation under present climate and sea-level conditions. With 1 m of sea-level rise likely to be reached between 2070 and 2130, approximately 75% of heritage land will be compromised by a 100-year storm inundation event. These results imply that heritage land at Te Pokohiwi ō Kupe is already susceptible to inundation by significant storm waves, with potential erosion and loss of archaeological sites becoming more severe as the sea level continues to rise over time.