- Address : 6, Imyeong-ro 131beon-gil, Gangneung-si, Gangwon-do
- Phone : (Gangneung Cultural art division) +82-033-640-5119
- Designation number : National treasure no. 51
- Designated date : December 20 1962
- Period : Late Goryeo dynasty
- Owner/manager : State-owned/ Gangneung city government (Cultural art division)
- Material : Wooden structure with tiled roof
- Scale/amount : 3 columns at the front, 2 columns at the side, Gable roof, Jusimpo structure
Gaeksa is one of the government office buildings in each town of Goryeo and Joseon. It keeps Jeonpae which represents king and people bowed toward the palace every first and 15th day of the month, and governmental officials dispatched by king stayed here. GangenungImyeonggwanSammun is the gate of Gaeksa.
GangenungImyeonggwanSammun is the gate of GanneungbuGaeksa(accommodation for guests or governmental officials) built in the 19th year of King Taejo of Goryeo (936). Total 93 rooms are in the building and named 'Imyeonggwan'. The nameplate "Imyeonggwan" was written by King Gongmin in his fifth year(1366) when he was going to Naksansa Temple. Now the name plate is moved to Jeondaecheong, the main building of Gaeksa.
The front is built with comparatively high stone stairs, arranged with natural rocks in a circular fashion. The foundation stones are all in different shapes. The front and back column is a distinctive circular Baeeullim(irregular thickness, upper and lower part of the column is thinner than the middle part), and the middle line columns are square column. Baeeulim of column is very distinctive than other buildings. It is the largest and very simple wooden cultural asset that still exists. It is supposed to be earlier than Soodeoksa Temple Daewoongjeon(built in 1308). It is the only designated national treasure structure in Gangwon-do, which has a simple Jusimpo style gable roofed Sammun.