jiangjie Border boundary Delimited territory of a State and territory boundaries with him the high seas. Also known as the boundary. Usually in the form of a treaty is determined by both parties, and the formation of a clear line on the map. Some border on the ground has clearly marked. Boundaries delineated boundaries on the ground in order to prevail, the line up and down the vertical boundaries constitute aerial and underground. Boundary problem is often an important cause of disputes and conflicts between countries, is very concerned about the political and geographical scientist topic. In ancient times, due to the development of the country has not yet reached the degree adjacent to each other, often exist between a rather wide zone countries, called the border. Modern border already replaced as a clear demarcation of the boundary line. Boundaries between general administrative divisions also called boundary. Follow signs to determine the boundary can be divided into natural boundaries and cultural boundaries. Natural boundaries tend to rivers, mountains, deserts and other natural elements as a symbol; humanities borders often language, ethnicity, religion and other cultural factors as a symbol. From the origin of the border, the two countries have not reached before actual contact is called first to determine the boundaries of the border; development in bilateral economic and _set_tlements reached after contact with each other to determine the boundaries of the overlay is called a boundary or boundaries. First to use more obvious natural boundary signs or latitude and longitude lines as borders, borders and more so neat straight. Such as the western United States and Canada geometric boundaries. Superimposed on the actual boundaries of multi-touch situation, or a minor adjustment is made, it borders tortuous, irregular. In fact, the boundaries of the world countries are mostly due to a combination of natural causes, cultural, political, and military formation. Among them, some are not very reasonable, thus causing the boundary dispute. (En Chung)