At the concourse is the diorama of Jeju-eupseong Fortress, and on the ceiling is a stained glass depicting the founding myth of Tamna (old name of Jeju).
Jeju-eupseong Fortress was reproduced based on a depiction in Tamna-sullyeokdo painted in the 28th year of King Sukjong's reign (1702), and the remains of old Jeju provincial government buildings that have been excavated since 1990. The stained glass of the ceiling shows Mt. Hallasan, the famous mountain of Jeju, a scene from Samseong Shinhwa, which is the founding myth of Tamna, and the Samdado (meaning "Island with an abundance of three things," which are rocks, wind, and women).