The hot springs were a location within the Iromish village on Hughes Island. They were a popular place to swim and party. Until 2033, the hot springs were maintained by Johan.
It was the first part of the Iromish village seen by James Zanasiu Jr, Malte Kerzach, and Florence Brennan when they became marooned on Hughes Island. A month later, Florence and Johan decided to leave the island while alone at the hot springs. ("CS:The Man Who Was an Island")