A subway line opened Monday in Kunming, capital of Southwest China's Yunnan Province, the first to be built in the area.

The 22-km-long line will eventually act as an overlapping section for two planned subway lines, a manager from subway operator Kunming Subway Co., Ltd. said.

The subway's trains will run at an average speed of 39.3 km per hour, taking 34 minutes for each one-way trip, the manager said.

Construction on the line started in April 2010. It went into trial operation on April 9 this year.