One of the most one-sided battles of the First Taranaki War (1860–61) was fought on the slopes of Mahoetahi on the morning of 6 November 1860. About 150 Maori who had come south from Waikato to support their Taranaki allies had just occupied an old pa site on the hill. Major-General Thomas Pratt sent columns from New Plymouth and Waitara to intercept this taua (war party), which had not had time to dig trenches. Most of the approximately 40 Maori killed were buried in a mass grave on the seaward side of the hill.
A walking track leads from the carpark at the road junction to the summit of the hill, on which a wooden memorial was erected about 1910 and replaced several decades later by a concrete one. In late summer the track is a narrow lane through maize which grows above head-high. There are views of Mt Taranaki, New Plymouth and Waitara.