The Rabaul caldera, or Rabaul Volcano, is a large volcano on the tip of the Gazelle Peninsula in East New Britain, Papua New Guinea, and derives its name from the town of Rabaul inside the caldera. The caldera has many sub-vents, Tavurvur being the most well known for its devastating eruptions over Rabaul. The outer flanks of the highest peak, a 688-metre-high asymmetrical pyroclastic shield, are formed by thick pyroclastic flow deposits. There is no sign of a pyroclastic shield along the rim of the caldera, making the location likely underwater, on the caldera's floor.
Tavurvur, a stratovolcano and a sub-vent of the caldera, is the most visibly active, continuously throwing ash. In 1994 it, and nearby Vulcan, erupted and devastated Rabaul; however, due to planning for such a catastrophe, the townsfolk were prepared and only five people were killed. One of the deaths was caused by lightning, a feature of volcanic ash clouds.
In 1937, Vulcan and Tavurvur erupted simultaneously, killing 507 people. This event led to the founding of the Rabaul Volcano Observatory which watches over the many active volcanoes on Papua New Guinea. One eruption over several days in March 2008 released a plume of ash and water vapor that drifted northwest over the Bismarck Sea.
Rabaul is a township in East New Britain province, on the island of New Britain, in the country of Papua New Guinea. New Britain is an island about 60 kilometres to the east of the island of New Guinea. Rabaul was the provincial capital and most important settlement in the province until it was destroyed in 1994 by falling ash of a volcanic eruption.
During the eruption, ash was sent thousands of metres into the air and the subsequent rain of ash caused 80% of the buildings in Rabaul to collapse. After the eruption the capital was moved to Kokopo, about 20 kilometres (12 mi) away. Rabaul is continually threatened by volcanic activity due to having been built on the edge of Rabaul caldera, a flooded caldera of a large pyroclastic shield.
Rabaul was known as Simpsonhafen during the German New Guinea administration which controlled the area between 1884 and formally till 1919. From 1910 Rabaul was the headquarters of German New Guinea until captured by the British Empire during World War I, when it became the capital of the Australian mandated Territory of New Guinea until 1937 when it was first destroyed by volcano.