Sejong the Great and Admiral Yi Sun-shin are great men in Korean history. King Sejong established Hangul. General Admiral Yi Sun-shin was a general in the Joseon Dynasty and led the navy in the Japanese invasion of Korea in 1592, and won every battle to make a big hit in defeating the army.
There are various exhibits. English commentary is also available, and it seems to be good for foreigners to watch. There are also a variety of experience centers.