10 Contested Border Sino-Korean border issue belonged to the second category.As the document pointed out,"[North]Korea built highways and houses on the contested area in Changbaishan.North Korea also built a cross-Yalu River water gate and is making a northward advance." A border survey in 1959"was conducted in accordance with the instructions of the CCP Central Committee...[and]played a supporting role for the diplomatic struggle and had focused on the Sino-Indian border"(Guangxi Autonomous Region Archive,X 50/3/37,85-89). As far as the Sino-Korean border was concerned,Jilin province conducted research on the inundated area in the Yalu River:put together information about the area's geography,the position of the main channel,and the border defense line for China and North Korea;and drew rough maps.The slow progress in surveying the Sino-Korean border was due to the 1959 Sino- Indian border clashes,which were a higher priority for the cen- tral government and slowed down work in other areas.Formal negotiations with fraternal socialist countries regarding border disputes had not yet started."To avoid provoking border inhabi- tants,"the boundary commission requested that "border surveys in provincial and local areas be kept secret."Regarding the work plan for 1960,the boundary commission anticipated no major problems regarding China's borders with socialist neighbors.As for the Sino-Korean border,the document pointed out:"Because it is not possible to resolve all the issues through negotiations,it is necessary to investigate the outstanding issue,i.e.,North Korea's northward activities.It is also necessary to propose a pro- visional and partial resolution"(Guangxi Autonomous Region Archive,X50/3/37,85-89). These documents help to clarify the Chinese government's position on resolving Sino-Korean border disputes in the early 1960s.First,they tell us that due to the existence of the Jiandao Treaty of 1909,no major dispute over demarcating the Sino- Korean border existed.Second,due to changes in the course of rivers and inundated areas,minor problems had appeared that required coming up with a partial solution.Third,problems had emerged "in demarcating the Sino-Korean boundary in the Changbaishan area"that could not be resolved in a short period