BEIJING -- Two new subway lines in Beijing are expected to break ground at the end of 2017, authorities said Thursday.

The combined length of the CBD Line and the branch line of Yanfang Line, both still being designed, will be around 12.6 km, according to the Beijing Major Projects Construction Headquarters Office.

The 6.5-km CBD Line will run between Dongdaqiao and Dajiaoting stations, with 8 stations planned. It will mainly serve passengers within the central business district and Beijing East Railway Station. The other line, about 6.1 km long, will have three stations. It will mainly serve passengers near Zhoukoudian Township in southwestern Beijing's Fangshan District.

Three other subway lines in Beijing will start operations within this year.