China's longest subway loop line, Line 12 of Wuhan Metro in Central China's Hubei Province, fully opens on October 29, 2026. Photo: Screenshot from China Media Group

China's longest subway loop line, Line 12 of Wuhan Metro in Central China's Hubei Province, fully opened on Thursday. With a total length of 59.9 kilometers and 37 underground stations, the line provides interchange access to 18 existing and planned metro lines.

The line runs through seven central urban districts, including Qiaokou, Jianghan and Jiang'an. It connects the two major railway hubs of Hankou Station and Wuchang Station. The whole journey through the loop would take about 96 minutes.

It was opened in two phases. Phase 1, spanning 35.3 kilometers, went into operation on May 1. The newly opened Phase 2 extends 24.6 kilometers and completes the full loop.

The line crosses under the Yangtze River twice and the Han River once. It features one of China's longest cross-river metro shield tunnels, and the builders overcame many construction challenges, including high water pressure, complex mixed strata, and long-distance underwater shield tunneling. It serves as a demonstration project for both cluster construction of cross-river metro tunnels and large-loop rail transit development.

The line also features Grade of Automation 4 level fully automated operation, the highest grade of automatic train operation in rail transit. Each morning, the trains wake up automatically, run self-diagnostics, and roll out of depots on their own. During service, they perform automatic turnbacks and station stops. Late at night, after operations end, they plan their own routes back to the depot and go into sleep mode. 

This entire "wake up-go to work-clock off-go to sleep" cycle requires no manual intervention, and the control center can take remote control at any time.

The trains have been specially trained. During peak hours, they automatically adjust headways, and in emergencies they can independently plan detours, taking on-time performance and emergency response to a new level.

The opening of Line 12 breaks the natural barriers of the Yangtze and Han rivers that have long constrained cross-river commutes. It will also support the development of a comprehensive transport hub in Wuhan city.

Global Times