Naewonsagyegok Valley is located just below Naewonsa Temple at the foot of Cheonseongsan Mountain. The valley is surrounded by Jeongjoksan Mountain to the northeast, Wonjeoksan Mountain to the south, and Cheonseongsan Mountain to the southeast. The water running through the numerous valleys between these mountains has formed streams like Yongyeoncheon and Sangnicheon, which form the Yangsancheon Stream out of Naewonsagyegok Valley.

Naewonsagyegok Valley was formerly called Sogeumgang (little Geumgang), meaning that its beautiful scenery is comparable to that of the breathtaking Geumgangsan Mountain. It is also known as the “mystical valley” as crystal clear water flows all year round. The word “Sogeumgang” is distinctly engraved on one side of the cliff and large rocks stand in layers throughout the valley. Some of the rocks are called Byeongpungbawi Rock, literally meaning folding screen rocks, as they are stretched out much like folding screens.

The valley and the surrounding mountains are a popular summer vacation spot and a well-known hiking destination during the spring, fall, and winter. Muk (acorn jelly) made with acorns gathered from this area not only tastes great, but is also very healthy. Nearby attractions include Tongdosa Temple and Hongnyongpokpo Falls.

* Entrance into the upper region of Naewonsagyegok Valley is restricted.