A shipwrecked traveler awakens aboard a gentle vessel among a chain of picturesque islands surrounding a broad inland sea and is taken into the care of graceful, capable inhabitants. He is escorted to communities that occupy both shores and two complementary cities at opposite ends of the mere, where officials and citizens receive him with respect. Guided conversations and encounters reveal a society organized around elevated social ideals, refined customs, and harmonious public arrangements, while vivid descriptions of landscape and daily life frame the visitor's slow comprehension of this ordered, Eden-like civilization.