Recently, the reconstruction of RenDingHu Park in Xicheng District, which costs 16 million Chinese yuan, has been completed. The first simulated man-made wetland in BeiJing also completed in the park. A lake which covers an area of 1 hectare and aquatic plants which covers an area of 3000 square meters clean and filter the water, 5.5 hectares of green land and 4000 trees purify and fertilize the air. The new Olympic flower-exhibition area becomes a new scene of the park.