Kerguelen Islands

Kerguelen Islands, also known as the Desolation Islands, are a group of islands in the southern Indian Ocean constituting one of the two emerged parts of the mostly submerged Kerguelen Plateau.

The Kerguelen Islands were used by Abstergo Industries for some sort of experiment, as it was "a nice place to keep it quiet".

Reference

 * Assassin's Creed III