Administrative divisions of the Tang dynasty
The Tang Dynasty administered the land using a hierarchical system of three descending divisions: circuit dào (道), prefecture zhōu (州), and county xiàn (縣). Prefectures have been called jùn 郡 as well as zhōu 州 interchangeably throughout history, leading to cases of confusion, but in reality their political status were the same . The prefectures were furthered classified as either Upper Prefectures (shàngzhōu 上州), Middle Prefectures (zhōngzhōu 中州), or Lower Prectures (xiàzhōu 下州) depending on population. An Upper Prefecture consisted of 40, 000 households and above, a Middle Precture 20, 000 households and above, and a Lower Prefecture anything below 20, 000 households. The scope and limits of each circuit's jurisdiction and authority differed greatly in practice, and often individual circuit governors' powers and autonomy grew to a point that the administrative system became popularly known as the ""Three Divisions of Falsehood"" (虛三級). As Tang territories expanded and contracted, edging closer to the period of Five Dynasties and Ten Kingdoms, administrative records of these divisions became poorer in quality, sometimes either missing or altogether nonexistent. Although the Tang administration ended with its fall, the circuit boundaries they set up survived to influence the Song Dynasty under a different name: lù (路).