Benefiting from Dujiangyan Irrigation Project which was constructed in 256 B.C., Sichuan Province is reputed as "Tian Fu Zhi Guo", literally a place richly endowed with natural resources. Chengdu, as the capital, is extremely productive. The Min and Tuo Rivers, two branches of the Yangtze River, connected to forty other rivers, supply an irrigation area of more than 700 square kilometers (270.27 square miles) with 150-180 million kilowatts of water. Consisting of abundant mineral resources, the land is extremely fertile. The history of Chengdu can be traced back 2,400 when the first emperor built his capital here and named the city. Through thousands of years its original name has been kept and its position as the capital and as the significant center of politics, commerce and military of the Sichuan area (once called Shu) has remained unchanged. Since the Han (206B.C.-220) and Tang (618-907) Dynasties when its handicraft industry flourished, Chengdu has been famous for its brocades and embroideries. Shu embroideries still enjoy a high reputation for their bright colors and delicate designs, ranking among the four main embroideries in China. Chengdu was the place where the bronze culture, an indispensable part of ancient Chinese culture, originated, the place where the Southern Silk Road started, and the place where the earliest paper currency, Jiaozi (not the dumpling!), was first printed. It is listed among the first 24 state-approved historical and cultural cities and owns 23 state and provincial cultural relic units.