In the 1960s, a military unit was stationed in the remote mountainous area of Western Sichuan, where they stayed for two decades. Among them were the parents of Yang Shu, a young boy from Beijing. At the age of eleven, Yang Shu was brought to the unit in the Sichuan mountains, since then an unforgettable chapter of his life has been unfolded. Everything within the compound of the unit was unfamiliar but fascinating to Yang Shu: the enigmatic air-raid shelters, the towering and treacherous peaks, the pristine Hongying School, and the bustling open-air cinema. He made friends with soldiers from the engineering battalion and a retired military dog, winning the trust and camaraderie of the children there. Beyond the compound, a tarred road led to the ancient town called Guqiao (which means ancient bridge), where the swaying bridge, the ancient character repository tower, the clear sounds of the bamboo zither, and the blooming osmanthus have all taken root in Yang Shu's memory. The title Green Mountain Ranges symbolizes the generation of author's parents, who spent their prime years in the verdant mountains. Just as stated in the narrative, "We are committed to dedicate our youth, our lives and those of our descendants to guarding our nation", which is a popular saying widely spread in the troops at the time.