Garove is the largest of the Witu Islands, which lie north of New Britain. The low, 12-km-wide elongated island is cut by a 5-km-wide caldera that is flooded by the sea through a narrow breach on the southern side of the island, forming Johann Albrecht harbor. The steep-sided caldera walls rise 100-150 m above the sea. Satellitic cones were constructed along the NE and SW coasts. No historical eruptions are known, but the preservation of fresh lava flow structures on the NW coast suggests an age as young as a few hundred years (Johnson and Blake, 1972). Fisher (1957) noted four thermal areas and a solfatara on the island.