China's single largest natural gas pipeline, the China-Russia east-route natural gas pipeline, is now fully operational. It can supply 38 billion cubic meters of natural gas annually to Northeast China, the Beijing-Tianjin-Hebei region and the Yangtze River Delta. The pipeline, which took nearly a decade to construct, stretches over 5,000 kilometers from northern China to the east coast. It crosses nine provincial-level administrative regions. It is also one of China's four strategic oil and gas import channels.