Eurimji Lake is located at the upstream valley and the lake sediments were initiated by the formation of by both natural levee and historical embankment.Based on sediment cores of representative boreholes,the lake sediments formed at latest 2000 a BP.It is also one of the oldest artificial reservoirs in the Korean history.A major construction of embankment was carried out at the about AD 800 during the Unified Silla Dynasty.The evidence materials found in the bank are composed of woods and gray organic muds,as well as burned clays pasted on the outer and inner walls of embankment.The origin of bank materials is lake bottom sediments.The lake bottom sediments formed older than 1200 a BP,showing a stable sedimentation pattern in the age interval of 1910 a BP and 1410 a BP.A sedimentation rate of the same interval is about 4 mm·a,which is relatively high compared to sedimentation regime of other paleo-lakes in Korea.This may be caused by catchment condition which is typified relatively by a strong runoff during the typhoon or stormy season annually.Lasdy it is presumed that untill the AD6 th century(Roman period) a paleohydrological system in middle Korean peninsula maintained annually stable even under the steep gradient of catchment landscape and surface processes. Eurimji Lake is located at the upstream valley and the lake sediments were formed by the formation of by both natural levee and historical embankment. Based on sediment cores of representative boreholes, the lake sediments formed at latest 2000 a BP. It is also one of the a major construction of embankment was carried out at the about AD 800 during the Unified Silla Dynasty. The evidence materials found in the bank are composed of woods and gray organic muds, as well as burned clays pasted on. the outer and inner walls of embankment. The origin of bank materials is lake bottom sediments. The lake bottom sediments formed older than 1200 a BP, showing a stable sedimentation pattern in the age interval of 1910 a BP and 1410 a BP. A sedimentation rate of the same interval is about 4 mm · a, which is relatively high compared to sedimentation regime of other paleo-lakes in Korea. This may be caused by catchment condition which is typified relatively b a strong runoff during the typhoon or stormy season annually. Lasdy it is presumed that untill the AD6 th century (Roman period) a paleohydrological system in middle Korean peninsula maintained annually even under the steep gradient of catchment landscape and surface processes.