In Star Wars: The Empire Strikes Back, the ice planet where the Rebels base is Hoth.
Hoth is the sixth planet in a remote star system and the location of the Rebel Alliance’s secret Echo Base. Its frozen surface, severe weather, and sparse wildlife make it a difficult place to find, helping the Rebels hide from the Galactic Empire.
The base is discovered after an Imperial probe droid sends a signal to Darth Vader’s fleet. The resulting Battle of Hoth begins with an Imperial assault using AT-AT walkers. Rebel snowspeeders delay the attack long enough for transports to evacuate personnel, though the base itself is lost.
Hoth is commonly mixed up with other memorable Star Wars worlds. Tatooine is Luke Skywalker’s desert homeworld, Endor is the forest moon associated with Return of the Jedi, and Jakku is introduced much later in the sequel trilogy. The film’s Hoth scenes were filmed partly at Finse, Norway, whose glaciers supplied the icy landscapes.