It’s time for us to fly to the Great Wall Of China. Actually, The Great Wall is a linked series of smaller defensive walls, the origins of which go as far back as the third century BC. The wall visitors see today was mostly built during the Ming dynasty, which ended in 1644. It runs about 4,000 miles in all. The Simatai section, 80 miles outside Beijing, features unrestored, hikable stretches of wall surrounded by green farmland, and is hailed as the most remote and spectacular viewing point. Or it would be, if not for the rarity of clear, sunny days in developed China, and Beijing in particular.
The original purpose of the Great Wall was to stop invaders from areas such as Mongolia and Manchuria, from entering China and trying to take over the country. The Wall spans 3,948 miles at the present time, and runs from Shanhai Pass on the Bohai Sea to Lop Nur in the Xinjiang Uygur Autonomous Region. It is made of solid stone with packed earth on the interior.
Increased levels of smog from vehicles, dust from the city’s many construction sites–which have multiplied as Beijing prepares for the 2008 Olympics–and wind-whipped sand particles from the nearby Gobi Desert conspire to pollute the air. Residents often wear white medical masks over their faces, and the Beijing Environmental Protection Bureau reportedly counted more days of severe air pollution in the first quarter of 2006 .
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