What is "tongaporutu"

Tongaporutu is a settlement in northern Taranaki, in the North Island of New Zealand. It is located on State Highway 3 at the mouth of the Tongaporutu River, 15 kilometres south of Mokau.Tongaporutu is well known in New Zealand for its 'Three Sisters' rock formations and its Maori petroglyphs carved into cave rock walls. However,both the Maori rock carvings and the 'Three Sisters formations are constantly being eroded by the Tasman sea.