"The most important issue is protecting Qinling Mountains," Deputy Director of Niubeiliang National Forest Park Management Committee Meng Ruyi said. Chinese President Xi Jinping visited Niubeiliang National Nature Reserve in Zhashui County in northwest China's Shaanxi Province. The reserve is located in the highest peak of the eastern segment of Qinling Mountains. Stressing ecological preservation, Xi told officials to learn from the lesson of illegal villas built in nature reserves in the Qinling Mountains and said they must be "ecological guardians" of the mountain's ecological system.