One mile, habit refers to a city, which is 500 meters. Li, the unit of length measurement. Since the reform of weights and measures was carried out from 65438 to 0929 in the Republic of China, one mile specifically refers to one city, which used to be called one mile.
Often used to measure distance and geographical distance. For example, milestones (signs set on the roadside for calculating mileage). As a unit of measurement, "Li" originated from China's ancient Jingtian system. After the abolition of the well field system, it evolved from an area unit to a length unit.
Extended data:
Metrological reform in the Republic of China;
The third change of the Chinese plum system occurred in the Republic of China: "1929, a city was defined as 150 feet, and the metric system was 500 meters. The system formulated this time is still in use today, which not only inherits the characteristics of China's traditional system, but also absorbs and combines the western metric system.
The so-called inheritance of the Chinese Li system is characterized by the fact that from the Zhou Dynasty, the traditional Li system in China was 300 steps per mile, but this time the Li system was 150 feet, and the five-foot step and two-step step step, 150 feet were exactly 300 steps.
The so-called absorption of the western metric system and its combination is as follows: "One city is 150 feet, and the metric system is 500 meters", that is, China's metric system is based on the western metric system, while China's city size is one third of that of the west. In this way, the two are integrated. Because the Li system formulated this time meets the needs of social development and is easy to convert with western length units, it is still in use today.
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