Both lines were envisioned to connect and promote development in the northeast regions of Guangzhou.

For example, several stations have passing loops to allow for express and local stopping patterns and trains reach a maximum service speed of 120 km/h (75 mph).

These considerations allow for passengers to travel from outer Guangzhou to the city center in one hour.

Cross Platform transfer will be provided at Tianhe Park station after reopening.

[7] There are 2 types of train services offered on the metro line 21: