In the past two years， deep canyons and steep cliffs were the worksites for Feng Zhiguo， an engineer with China Railway Major Bridge Reconnaissance and Design Institute Co. Ltd.， a company famous for designing large bridges.
　　While working as a project manager tasked with finding sites to anchor the piers of a gigantic bridge on the Nujiang River， he got the nickname “antelope” for his adeptness at scaling mountains. Every day， Feng walked for hours in the mountains， conducting geological survey.
　　The bridge will be one of the numerous ones to be built for the Sichuan-Tibet Railway， the second rail route into Tibet Autonomous Region in southwest China.
　　Feng joined the project in 2018， in preparation for building the railway’s middle section linking Yaan in Sichuan Province and Nyingchi in Tibet. The construction officially started on November 8.
　　The railway will play an important role in safeguarding national unity， promoting ethnic solidarity and consolidating stability in border areas， President Xi Jinping said， adding that it will also contribute significantly to the economic and social development of the western region， especially Sichuan and Tibet.
　　“It is an honor for me to participate in this project of a century. It can help improve our work，” Feng said.

A challenging project

　　The 1，600-km railway is expected to shorten the travel time between Chengdu， capital of Sichuan， and Lhasa， capital of Tibet， from 48 hours to 13. It is divided into three sections. The eastern section， from Chengdu to Yaan was put into operation in December 2018. The construction of the western section， from Lhasa to Nyingchi in Tibet， started in 2015， and has been progressing smoothly. The middle section has a designed length of 1，011 km and speed of 120 km to 200 km per hour.
　　More than 80 percent of the railway will pass through either tunnels or bridges， with a cumulative ascent equivalent to twice the height of Mount Qomolangma， the world’s highest peak at 8，844.43 meters above sea level， said Xia Lie， a senior engineer at China Railway Eryuan Engineering Group and a key designer of the railway. Xia likened it to a colossal roller coaster through mountains and canyons.
　　The middle section is believed to be one of the most challenging railway projects in the world because it will zigzag through towering mountains and turbulent rivers lying between the Sichuan Basin and the Qinghai-Tibet Plateau. It is expected to be completed in seven years. 　　“It will go over 21 snowcapped mountains more than 4，000 meters above sea level and cross 14 major rivers，” You Yong， chief engineer of the Institute of Mountain Hazards and Environment of the Chinese Academy of Sciences， told Xinhua News Agency.
　　The section crosses the Nujiang in Qamdo， a city in Tibet. Literally known as the “Angry River，” the river got its name for its loud rapids that can be heard far away during the rainy season.
　　At the segment near Tongka Town in Qamdo， the river runs between ridges rising more than 4，000 meters above sea level. At such a high altitude， walking a long distance is exhausting. Feng had to have a break from time to time. The roads chiseled out of cliffs are rough and narrow. Though months had passed， he said he shivered with fear when thinking about traveling on a section that is only half a meter wide on the edge of a cliff.
　　While in the wilderness， Feng had to watch time carefully to make sure that he and his colleagues could return to their base in the evening. If they spent the night out， they would not only suffer low temperature， but also risk attacks by animals.
　　After picking a site， there would still be a lot of things to do. A drilling rig would be hoisted to the top of the mountain， and rock samples would be collected and analyzed in preparation for the design and construction of the bridge.
　　In addition to the rugged terrain， the railway will face other hazards such as avalanches， landslides and earthquakes. It will go through seismic belts， You said.
　　Natural disasters have caused serious damage to the region. In 2000， a huge landslide destroyed all bridges， roads and telecommunications facilities built over the previous four decades in the affected areas in Bomi County， Tibet.

　　In 2008， an 8-magnitude earthquake struck Wenchuan， a county in Sichuan， causing serious damage to infrastructure in the region.
　　Researchers such as You have been monitoring and analyzing possible hazards and offered advice on route selection and precautions needed.

Getting connected

　　Although the construction of the middle section has just started， Gonjo Chodron， an official with Zhari Township in Shannan， Tibet， is already looking forward to welcoming tourists who will arrive by train.
　　“We are ready to welcome guests，” she told the media while attending the annual conference of the National Committee of the Chinese People’s Political Consultative Conference in Beijing in May. She said her hometown is a picturesque place， yet poor infrastructure hampered the development of tourism. 　　Situated on the “roof of the world，” Tibet was isolated from the rest of the world in the past. There was no modern road into Tibet until 1954， the year when two paved roads， respectively from neighboring provinces of Qinghai and Sichuan， were open to traffic. In 1965， Tibet’s first air route was launched， which connects Lhasa to Chengdu.
　　After the first railroad into Tibet， the Qinghai-Tibet Railway， went into operation in 2006， the region’s development， including transportation， picked up steam. In 2013， Medog became the last county in China to have access to highways.
　　A railroad was completed within Tibet in 2014， connecting Lhasa with Xigaze， the region’s second largest city. As of March， the region had five airports and 103 air routes reaching 51 cities at home and abroad.
　　Gonjo Chodron said she is looking forward to the early operation of the SichuanTibet Railway， which she believes will be of great significance to the development of Tibet. The railway will not only facilitate the transportation of passengers and goods， but also bring Tibet and the outside world closer， she said.