Summarize Qin Shihuang's measures to govern the frontier and point out its positive significance.

Qin Shihuang's measures to govern the frontier: immigration, building cities and setting counties. Significance: spreading advanced culture and production technology of Han nationality; Promote the development of border areas; Promote national integration; Open up the territory; Establish a multi-ethnic unified country.

Qin Shihuang conquered South Vietnam and incorporated Fujian, Zhejiang and Guangdong into Chinese territory. Attack the Huns in the north and recapture the Hetao area, making this area the territory of China forever. East to the sea and Korea, west to Lintao and Zhong Qiang, south to the south of the Tropic of Cancer, north to Sai, and Yinshan to Liaodong. In addition, Qin Shihuang also opened Wuchi Road to the southwest, roughly from Yibin, Sichuan to Qujing, Yunnan, controlling the local tribal countries and extending his regime to the Yunnan-Guizhou Plateau.

Qin Shihuang's exploration of remote areas such as southeast, south-east, southwest and north has great and far-reaching significance both in the history of China and in the history of the world. The Qin Dynasty is so famous that "Qin people" have long been synonymous with China. In ancient Indian Sanskrit, China was called "zhina", and the geography book of Greek geographer Ptolemy included "Chinni" country. Even today, Europeans still call China China. These all come from the pronunciation of the word "Qin".

So far, the basic pattern of China's unified multi-ethnic centralized state has been established.