Studies of Buddhist statues in the Namhan River basin demonstrate that this region served as a crucial venue for Buddhist art exchange from the late Silla to the early Goryeo Dynasties. The Buddhist statues discovered in this region can be largely divided into two types: those inheriting the traditional style of the Unified Silla period and those reflecting the iconography newly emerged in the early Goryeo Dynasty.
Representative examples of Buddhist statues inheriting the Unified Silla style include the Standing Stone Buddha at Yongbuwon-ri Temple Site in Danyang and the Standing Stone Buddha at Wonpyeong-ri Temple Site in Chungju. The Standing Stone Buddha at Yongbuwon-ri Temple Site in Danyang is a colossal statue, over four meters tall, clad in a robe of the Ujeonwangsang style, with a V-shape group expressed on the lower body and it is important as an early example of Standing Stone Buddha statues wearing a coronal in that there is a coronal with a circular hole atop its head. The Standing Stone Buddha at Wonpyeong-ri Temple Site in Chungju also generally has a style of the late Unified Silla period, but because of its smaller body ratio (4-5 head figure) and more advanced formalization, it is estimated to have been produced in the early Goryeo Dynasty. This Buddhist statue inherits the tradition of standing stone Buddhas in the royal capital region, such as the late 7th-century Wangjeonggol Standing Stone Buddha in Namsan, Gyeongju, and the 8th-9th-century Janghang-ri and Satgatgol Standing Stone Buddhas in Gyeongju.
On the other hand, new iconographic Buddha statues created in the Namhangang River basin during the early Goryeo period demonstrate the process through which the royal capital's Buddhist statue style was handed down to a region and naturalized. The type of Yeongpari Standing Stone Bodhisattva Statue in Haeju is characterized by having the highly knotted hair without any coronal and wearing a robe resembling the Ujeonwangsang style, and it is suggested to be a Maitreya Bodhisattva statue. This type is stylistically connected to the standing stone bodhisattva statues in Jingwan-dong and Sangbuam in Seoul, Sinseonam and Maejiri in Wonju. It is distributed throughout areas near the Goryeo capital, Gaeseong such as Haeju, Seoul, Wonju, and along the waterways of the Namhangang River. Buddhist statues of the same style created in the Wonju area, such as the Maejiri Standing Stone Bodhisattva, exhibit modified features such as a fleshy face, a rounded body, and the left hand resting on the thigh. This is understood to be the result of the gradual naturalization of similar Buddhist statues with a strong regional character. The Dogokri Seated Stone Buddha in Yeoju is a representative example of Maitreya Buddha iconography produced during the period when Buddhist culture was introduced to Gaeseong via the Namhangang waterway. The special hand gesture, with the ring and little fingers of the right hand straightened, closely resembles the Seated Stone Buddha at Hyeonhwasa Temple site in Gaeseong. Given that Hyeonhwasa Temple was the headquarters of the East Asian Yogācāra and revered Maitreya as its primary deity, this is highly likely to be a Maitreya iconography. This Buddhist statue is directly connected to the Namhangang River waterway and is assumed to have been produced amidst the frequent exchanges between royal families, aristocrats, and eminent monks.
The Namhangang River basin Buddhist statues are a significant cultural heritage, demonstrating the succession, transformation, and fusion of Unified Silla and Goryeo Buddhist statue styles within a single cultural sphere. Through studies of these Buddhist statues, the process of spread and transformation of Buddhist art, the inter-regional stylistic exchanges, and the phenomenon of naturalization at the time can be more clearly understood.