Orakei Korako (Māori for "The Place of Adorning"), is a highly active geothermal area most notable for its series of fault-stepped sinter terraces, located in a valley north of Taupo on the banks of the Waikato River in the Taupo Volcanic Zone, New Zealand. It is also known as “The Hidden Valley”.
From earliest times the Waikato Valley near Orakei Korako was occupied by Māori of the Ngāti Tahu sub-tribe of Tuwharetoa. By the early 19th century the Māori population had congregated at Orakei Korako, probably attracted by the hot springs, which they used for cooking and bathing. The date when the Ngāti Tahu vacated the valley to settle at other locations is not recorded, but it has been suggested that they left after the eruption of Mount Tarawera in 1886, when great changes are alleged to have occurred in the hot springs. By the turn of the 20th century all but two families had moved from Orakei Korako.
The earliest known route from Rotorua to Taupo for early European travellers passed right through Orakei Korako, and it was the existing Māori who provided a dugout canoe for the river crossings. It was at this point in the early 20th century that the geothermal area was established as a visitor attraction. To transfer visitors across the then-swift Waikato River they used the dugout canoe, until in the 1930s a wire-strop and pulley system was erected across the river, and a punt with a guiding rudder was used to catch the flow and propel the punt to the other side. The tourist resort was officially opened on 15 December 1937.
The first proposal for power development at Orakei Korako was made in 1904, but it wasn’t until 1955 that the scheme was finally approved. By May 1960 an earth-filled dam, rising 49 metres above the original river level, was placed and consolidated. The filling of Lake Ohakuri began on 19 January 1961 and was completed in 14 days.