<Tr> <Th_colspan="2"> Basin features </Th> </Tr> <Tr> <Th> Basin size </Th> <Td> 13,701 km (5,290 sq mi) to Mercer </Td> </Tr> <P> The Waikato River is the longest river in New Zealand, running for 425 kilometres (264 mi) through the North Island . It rises in the eastern slopes of Mount Ruapehu, joining the Tongariro River system and flowing through Lake Taupo, New Zealand's largest lake . It then drains Taupo at the lake's northeastern edge, creates the Huka Falls, and flows northwest through the Waikato Plains . It empties into the Tasman Sea south of Auckland, at Port Waikato . It gives its name to the Waikato Region that surrounds the Waikato Plains . The present course of the river was largely formed about 17,000 years ago . Contributing factors were climate warming, forest being reestablished in the river headwaters and the deepening, rather than widening, of the existing river channel . The channel was gradually eroded as far up river as Piarere, leaving the old Hinuera channel high and dry . The remains of the old river path can be clearly seen at Hinuera where the cliffs mark the ancient river edges . The river's main tributary is the Waipa River, which has its confluence with the Waikato at Ngaruawahia . </P> <P> The name Waikato comes from the Māori language and translates as flowing water . </P>

Where does the waikato river begin and end
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