Rabaul is a low-lying caldera situated on the tip of the Gazelle Peninsula in the sub-region, New Britain that lies in the Country of Papua New Guinea. Rabaul caldera, a large volcano of the east New Britain, got its name from the town of Rabaul that was sited inside the caldera. The summit elevation of the highest peaks of the volcano is 688 meters is 2,257 ft which is a lop-sided pyroclastic shield volcano.
Before the major volcanic eruption of 1994, Rabaul has a sheltered harbor known as the Simpson Harbor that was in use by Rabaul, largest city of the island. The present caldera is 8 x 14 km is broadly breached on its eastern side and its floor is occupied by the Blanche Bay. Rabaul caldera was formed more than 1400 years ago and the eruption before 1994 occurred some 7100 years ago. It was said to originate from the Tavui caldera located offshore in its northern end. There are three more strata volcanoes on the northern and north east rims of Rabaul.
The cones of the caldera are basaltic and include Vulcan cone and was said to have produced major explosive activity in the historical past. A furious explosive eruption that occurred in 1994 in Rabaul were from the Vulcan and Tavurvur volcanoes and the entire town of Rabaul with the Simpson Harbor and area around Karavia Bay was masked in volcanic ash. Today, the then beautiful landscape is abridged into an unknown prehistoric desert. The volcano is still active and huge spiral of smoke is still noticed into the sky.