Sichuan was ruled by Kingdoms of Ba and Shu. After the first emperor of the Qin Dynasty unified China (221 B.C.), Shu and Ba Prefectures were set up here. In 1001 (during the Song Dynasty) it was divided into four administrative zones — Yizhoulu (for Chengdu), Zizhoulu (for Santai), Lizhoulu (for Guangyuan) and Kuizhoulu (for Fengjie). These four Lu was called “four ravine lu” which is the origin of Sichuan (In Chinese it means means “four ravines”). In the year of 1286 during the reign of Kublai Khan, the first emperor of the Yuan Dynasty, it was formally designated as a province.