Da Danyang is located in Zhenjiang City, Jiangsu Province, and Xiao Danyang is located at the junction of Anhui and Jiangsu. There are obvious geographical differences between them. Da Danyang is famous for its glasses industry and is an important base of the global glasses industry, while Xiao Danyang's glasses industry is not famous. Da Danyang also has a high reputation in the auto parts industry, while Xiao Danyang's auto parts industry is not famous.