China National Highway 221 (221国道) runs from Harbin to Tongjiang, in Heilongjiang Province. It is 668 kilometres in length and runs northeast from Harbin towards Tongjiang.[1]
^山东省地图出版社; Shandong Sheng di tu chu ban she; 北京天域北斗图书有限公司 (2001). 中国高速公路及城乡公路网地图集. 北斗地图系列 (in Chinese). 山东省地图出版社. p. 61. ISBN978-7-80532-486-9. Retrieved 2024-05-06.
China National Highway 112 runs around Beijing
Before 2013, Mainland China observed National Highway 228 as Taiwan Ring, composed of several National Expressway (Republic of China) and Taiwan provincial highways, this designation is not recognized by Republic of China (Taiwan). This observation was eventually dropped in new National Highway plans, replaced by Dandong-Dongxing Highway.
A extension plan of the highway system was announced in 2013, including extension of existing highways(101-112, 201-227, 301-330) and new highways (North-South 228-248, East-West 331-361, Connections 501-581). Only small portions of them needs to be constructed from scratch; most of the new highways would be upgraded provincial/county highways.
Another extension plan was announced in 2022, including new small purpose connection highways (601-701).