Passengers walk off the airstairs as their jumbo jet of Boeing 737 lands on the tarmac of the Yulong Airport of Chifeng City, in its maiden flight of round way air service operated by the China Southern Airlines Co.,Ltd connecting Guangzhou-Hohhot-Chifeng which is formally launched as of the day, in Chifeng, north China's Inner Mongolia Autonomous Region, March 28, 2010.[Photo/Xinhua]