The Joinville Island group—which includes D'Urville Island, Joinville Island, Dundee Island and Bransfield Island—is a group of Antarctic islands separated from the northeastern tip of the Antarctic Peninsula by the Antarctic Sound. Joinville Island is the largest of them. D’Urville takes its name from the leader of the French expedition that discovered the islands in 1838. Captain Jules Dumont d'Urville, a French naval officer and rear admiral who explored the south and western Pacific, Australia, New Zealand and Antarctica, led an expedition of two ships, the Astrolabe and the Zélée, to learn about the continent and its thoroughfares. Two weeks after sighting its first iceberg, the expedition became entangled in a mass of ice that prevented the ships from continuing south. Over the course of two months, d’Urville spearheaded several attempts to find a passage through the ice. Each time an ice-free channel was found, the wind shifted and trapped the expedition in a new set of icebergs. The ships eventually reached the South Orkney Islands and then the South Shetland Islands, and finally discovered the Joinville Island group. Conditions on board had grown so desperate by that point—with crew members suffering from scurvy—that d’Urville shifted course for Chile, where he established a temporary hospital for his crew.