Chinese name: Beijing mbth: Beijing Hanyu Pinyin: běijng Jurisdiction: 12 District 2 County 289 Township area:1641square kilometer Center: 39 degrees 54 minutes north latitude, east longitude 165438. The elevation of Beijing Plain is 20-60m, and the mountainous area is generally 1 0,000-10,500m. Geography The center of Beijing is located at 39 degrees 54 minutes north latitude and 1 16 degrees 23 minutes east longitude. Located on the northwest edge of North China Plain. Beijing is adjacent to Tianjin and is surrounded by Hebei Province together with Tianjin. Beijing is surrounded by mountains in the west, north and northeast, and the Beijing Plain slowly inclines to the Bohai Sea in the southeast. Dongling Mountain, which borders Hebei, is 2303 meters above sea level and is the highest peak in Beijing. The territory flows through five major rivers, mainly Chaobai River and North Canal in the east, Yongding River and Juma River in the west. The terrain of Beijing is high in the northwest and low in the southeast. The western part is the Western Mountain of Taihang Mountain, and the northern part is Du Jun of Yanshan Mountain. The two mountains intersect at the south exit of Guangou, forming a semi-circular mountain bend that spreads to the southeast. People call it "Beijing bend", and the small plain it surrounds is the Beijing small plain. Look at the topography of Beijing, which is surrounded by mountains and seas, and the situation is magnificent. As the ancients said: "The land of Youzhou has the sea on the left, the Taihang Mountain on the right, the Yongjiang River in the north, the big river in the south and the land of abundance." Maximum accuracy The shortest distance on a picture that a person with normal vision can distinguish with the naked eye is 0.1mm.. Therefore, the horizontal length of the field equivalent to 0. 1 mm on the map is the most accurate limit that can be expressed on the map, which is called the maximum accuracy of the scale. The following table shows the maximum accuracy of the national basic scale topographic map: scale1:1:25001:5001:65438+1:25001:50065438. 12.5510 2550100 development trend since the beginning of the new century, with the continuous popularization of the internet, maps have moved from paper to the internet, personal computers and even handheld devices. Nowadays, people can easily search for places of interest on electronic maps, which greatly facilitates map users. In addition to traditional geographic information services, major map and content providers have also developed many interesting applications based on electronic maps. Nowadays, electronic maps are becoming more and more common tools for people. It can be predicted that in the future, electronic maps will be integrated with more applications, and more 3D technologies and satellite technologies will be applied, making people's travel and daily life more convenient. The rise of electronic maps With the increasing popularity of the Internet, maps have moved from paper to the Internet, personal computers and handheld devices. People can easily search for places of interest, driving routes and bus routes in the electronic map, and provide reference suggestions for travel arrangements. Well-known electronic map websites include Baidu map, Google map, Gaode map, 5 1 map, e city, etc., to meet the information needs of public travel and daily life. Since 2006, with the in-depth development of the Internet, local life search websites based on maps have gradually emerged. These websites rely on electronic maps to provide various life information to the public, such as Aibang.com, Pinmi.com, Dianping.com and Google Life Search. In addition to the traditional two-dimensional electronic map, there are more map innovations on the Internet. Google Earth arranges satellite photos, aerial photos and GIS on the three-dimensional model of the earth to provide users with high-definition satellite photos from all over the world for free. E City presents the world's first three-dimensional simulation city to the public, and deduces the real city life in the virtual network world. Similar innovations include data map network, which helps users to make various maps based on data, which can be easily enjoyed. Beijing map