The island is bounded in the east by Evans Cove and the Hells Gate Moraine, and in the west by the Nansen Ice Sheet.

In March 1912 the party excavated a small 3.7-by-2.7-metre (12 by 9 ft) ice cave in a snow drift they nicknamed "Inexpressible Island" where they spent the winter in miserable conditions, supplementing their rations by killing scarce seal and penguins for meat.

The Northern Party had previously built a supply depot at Hells Gate Moraine (74° 52'S, 163° 50'E) on Inexpressible Island as a form of security should the Terra Nova be unable to collect them.

Despite the fact that this depot had been built, the winter spent in the ice cave and a partially constructed rock shelter on Inexpressible Island was miserable.

"The men started home for Hut Point on September 30, 1912, some two hundred miles down the coast, which would include the crossing of the Drygalski Ice Tongue.

[8][9] A 365-hectare (900-acre) site comprising ice-free ground on the eastern shore of the island has been designated an Important Bird Area (IBA) by BirdLife International, because it supports about 24,000 breeding pairs of Adélie penguins and some 60 pairs of south polar skuas which breed in the vicinity of the penguin colony.