The Rotorua Caldera is a large rhyolitic caldera that is filled by Lake Rotorua. It was formed by an eruption 240,000 years ago that produced extensive pyroclastic deposits. Smaller eruptions have occurred in the caldera since, the most recent less than 25,000 years ago. It is one of several large volcanoes in the Taupō Volcanic Zone on the North Island of New Zealand.

The Taupō Volcanic Zone (TVZ) is a volcanic area in the North Island of New Zealand that has been active for at least the past two million years and is still highly active. Mount Ruapehu marks its south-western end and the zone runs north-eastward through the Taupō and Rotorua areas and offshore into the Bay of Plenty. It is part of a larger Central Volcanic Region that extends to the Coromandel Peninsula and has been active for four million years. The zone is contained within the tectonic intra-arc continental Taupō Rift and this rift volcanic zone is widening unevenly east–west with the greatest rate of widening at the Bay of Plenty coast, the least at Mount Ruapehu and a rate of about 8 mm (0.31 in) per year at Taupō. The zone is named after Lake Taupō, the flooded caldera of the largest volcano in the zone, the Taupō Volcano and contains a large central volcanic plateau as well as other landforms.