The turtle ship was a type of warship used by the Korean navy during the late 16th century, particularly in the Imjin War against Japan. Designed by the admiral Yi Sun-sin, these ships were notable for their unique, covered design that resembled a turtle's shell. This structure provided protection for the crew and made it difficult for enemies to board. Turtle ships were equipped with various weapons, including cannons and spikes on the roof to deter attackers. Their innovative design and effective use in naval battles contributed significantly to Korea's defense and naval strategy during this tumultuous period in history.