King Sejong The Great Museum

King Sejong the Great Museum in Seoul's Dongdaemun-gu is a public institutional museum on King Sejong the Great (1397-1450), the 4th king of the Joseon Dynasty and one of the most historically significant Korean monarchs — particularly for his creation of Hangul (1443, promulgated 1446) and his substantial patronage of scientific, cultural, and administrative reforms during his 32-year reign. The museum operates as a companion institution to The Story of King Sejong underground exhibition (batch 1 verified — the Gwanghwamun Plaza underground exhibition), and provides deeper research-and-scholarship coverage of Sejong's biography and works. Permanent exhibits combine period documents (facsimile), scientific-instrument reconstructions (Honcheonui armillary sphere, Cheugugi rain gauge, sun-and-water clock reconstructions), Hangul creation-and-promulgation documentation, and interpretive material on Sejong's court-system reforms. The museum's specific scholarship-oriented character makes it a more substantial resource than the Gwanghwamun underground exhibition for travelers with deeper interest in Sejong. Bilingual Korean/English interpretation. Free entry. Allow about 90 minutes. Access: 10-minute walk from Cheongnyangni Station (Line 1). Pair with the batch 1 verified the-story-of-king-sejong (Gwanghwamun underground exhibition) for the deeper research-plus-immersive combination, and with the broader Seoul central heritage circuit.