It runs to approximately 2606 km, and, on a map, runs southeast towards Nanjing and Hangzhou before turning south-southwest at Taizhou. In 2013, under a new 2013-2030 plan by NDRC&MoT, the G102 has been extended to Pingtan.
Leaving Beijing, it first runs as part of South Zhongzhou Road and is also known as Nanyuan Road (for being close to the Nanyuan area). However, it then diverts southwest and becomes the highway unto itself.
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).