December 26, 1962 (30 Renyin the winter months), the signing of the Sino-Mongolian border treaty. Reference in 1962 12, 26, 2010, the Sino-Mongolian border treaty signed in Beijing. March 25, 1963, in force after ratification of Ulaanbaatar interchangeable. Main elements: two parties to the trend of the boundary line of the two countries; parties agree that a lot bounded to the river as the boundary of the main stream of the river centerline, where the road to the lots bounded the road for both parties if by mutual management and use; Both sides agreed that immediately after the entry into force of the Treaty, the establishment of the Sino-Mongolian joint demarcation committee, specific survey the whole of the boundary between the two countries, erection of boundary markers, and then the drafting of the Protocol on the border between the two countries and draw a boundary map contain full details of the direction of the boundary line and the location of the boundary markers, instead of the map annexed to this Treaty. The bilateral border Protocol signed on June 30, 1964.