The trip lasted 9 months during which time they visited the Canary Islands, Cameroon, Cape Town, (where he joined Rudolf Marloth on collecting trips in the southern Cape), Kerguelen, New Amsterdam and Cocos Islands, Sumatra, the Maldives, Ceylon, the Seychelles and the Red Sea.
But also in New Guinea, South Africa, Australia, New Zealand, Alaska, St. Paul Island (Indian Ocean), Antarctic and subantarctic islands such as the Graham Land, Kerguelen, Macquarie Island, South Georgia, and the South Orkney Islands.
In 1772, Kerguelen-Trémarec and the naturalist Jean Guillaume Bruguière sailed to Antarctica in search of the fabled Terra Australis. There he took possession of various territories for France including what would later be called the Kerguelen Islands.
Rallier du Baty is commemorated in several geographic features, including Péninsule Rallier du Baty in the Kerguelen Archipelago, and Rallier Island and Rallier Channel in the Wilhelm Archipelago of the Antarctic Peninsula.