The Waikato-Hauraki region is an extensive area of lowland some 55 miles wide and 70 miles in length to the south of Auckland. Bounded in the east and south by the Coromandel, Kaimai, and Mamaku Ranges and the edge of the Central Plateau, it reaches the Tasman Sea between Raglan Harbour and the mouth of the Waikato River. The six counties, Hauraki Plains, Piako, Matamata, Waipa, Waikato, and Raglan, correspond roughly to these boundaries and, together with their interior boroughs and cities, they constitute the principal basis for the collection of statistics. The Hamilton Urban Area (population 50,505, 1961) is the leading city of the region which in 1961 had a total population of 167,693 (6·93 per cent of the national total) of which 9·15 per cent were classed as Maoris.