Wai-O-Tapu Thermal Wonderland is an active geothermal area at the southern end of the Okataina Volcanic Center. Before the arrival of Europeans, it was the home of the Ngati Whaoa tribe. The name Wai-O-Tapu in the Maori language means "sacred waters". It lies north of the Reporoa Caldera, in the New Zealand volcanic zone of Taupo. It has an area of 18 km2 and is 27 kilometers from Rotorua. The geothermal area was formed by the collapse of a volcanic crater about 200,000 years ago. It has been a protected scenic reserve since 1931. Later, part of the reservation was set aside for tourist activities. Due to the favorable geothermal conditions, Wai-O-Tapu has a number of hot springs, characterized by their colors. The most famous places are Lady Knox Geyser, Champagne Pool, Artist's Palette, Primrose Terrace and boiling mud pools.