Manyeonsa Precambrian granitic gneiss makes up the bedrock of Mudeungsan. It is a geosite where geological history of Mudeungsan (since the Precambrian era) can be observed. The outcroppings of the Precambrian granitic gneiss are severely weathered and of poor quality. These are not easily observed as the hills are in old age like those in the Gwangju area. However, the site is regarded as a geosite as it makes up the bedrock of the mountain and provide geological history before the formation of Mudeungsan.