Taupo's largest eruption occurred 26,500 years ago producing 300km³ of Ignimbrite (from pyroclastic flows) 500km³ of pumice and ash and an unknown volume of material inside the caldera. There was a large lake already present at the time but this eruption is thought to have created the caldera now filled by Lake Taupo. Lake Taupo covers about 600km².

The last eruption in 181 AD - about 1800 years ago was unusually violent, throwing out about 100km³ of material. A large and very energetic pyroclastic flow finished the eruption which devastated an area of about 20,000km², and filled all the major river valleys of the Central North Island with pumice and ash. Rounded pumice found on the beaches around the North Island come from this eruption. The ash in the atmosphere was recorded at the time by both the Romans and Chinese.