<P> Since the early 1980s, the urban area of Beijing has expanded greatly with the completion of the 2nd Ring Road in 1981 and the subsequent addition of the 3rd, 4th, 5th and 6th Ring Roads . According to one 2005 newspaper report, the size of newly developed Beijing was one - and - a-half times larger than before . Wangfujing and Xidan have developed into flourishing shopping districts, while Zhongguancun has become a major center of electronics in China . In recent years, the expansion of Beijing has also brought to the forefront some problems of urbanization, such as heavy traffic, poor air quality, the loss of historic neighborhoods, and a significant influx of migrant workers from less - developed rural areas of the country . Beijing has also been the location of many significant events in recent Chinese history, principally the Tiananmen Square protests of 1989 . The city has also hosted major international events, including the 2008 Summer Olympics and the 2015 World Championships in Athletics . </P> <P> Beijing is situated at the northern tip of the roughly triangular North China Plain, which opens to the south and east of the city . Mountains to the north, northwest and west shield the city and northern China's agricultural heartland from the encroaching desert steppes . The northwestern part of the municipality, especially Yanqing County and Huairou District, are dominated by the Jundu Mountains, while the western part is framed by Xishan or the Western Hills . The Great Wall of China across the northern part of Beijing Municipality was built on the rugged topography to defend against nomadic incursions from the steppes . Mount Dongling, in the Western Hills and on the border with Hebei, is the municipality's highest point, with an altitude of 2,303 metres (7,556 ft). </P> <P> Major rivers flowing through the municipality, including the Chaobai, Yongding, Juma, are all tributaries in the Hai River system, and flow in a southeasterly direction . The Miyun Reservoir, on the upper reaches of the Chaobai River, is the largest reservoir within the municipality . Beijing is also the northern terminus of the Grand Canal to Hangzhou, which was built over 1,400 years ago as a transportation route, and the South--North Water Transfer Project, constructed in the past decade to bring water from the Yangtze River basin . </P> <P> The urban area of Beijing, on the plains in the south - central of the municipality with elevation of 40 to 60 metres (130--200 feet), occupies a relatively small but expanding portion of the municipality's area . The city spreads out in concentric ring roads . The Second Ring Road traces the old city walls and the Sixth Ring Road connects satellite towns in the surrounding suburbs . Tian'anmen and Tian'anmen Square are at the center of Beijing, directly to the south of the Forbidden City, the former residence of the emperors of China . To the west of Tian'anmen is Zhongnanhai, the residence of China's current leaders . Chang'an Avenue, which cuts between Tiananmen and the Square, forms the city's main east - west axis . </P>

River in china near the capital city of beijing
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