It lies on the seaward end of the Colville Channel, 15 km (9.3 mi) north of the Mercury Islands and approximately 23 km (14 mi) south-east of Great Barrier Island.

The 195 ha (480 acres)[2] island is a wildlife sanctuary, managed by the Department of Conservation and is the subject of an ongoing island restoration project to eliminate non-native mammals and restore the original ecosystem.

[3] It is also the location of the Cuvier Island Lighthouse which was constructed in 1889 and the wreck of the old HMNZS Philomel which was scuttled near the island on 6 August 1949 after decommissioning and being stripped of useful equipment.

The island is the remains of an igneous intrusion of the Coromandel Volcanic Zone, which formed during the Miocene between 17 and 16 million years ago.

[4] The island has been identified as an Important Bird Area by BirdLife International because of its small breeding colony of vulnerable Pycroft's petrels.