The first operation of Qinghai–Tibet Railway is conducted in China

On July 1, 2006, the Qinghai–Tibet Railway, one of the most ambitious and technically challenging rail projects in human history, officially began operations in China. Spanning 1,956 kilometers (1,215 miles) from Xining, in Qinghai Province, to Lhasa, the capital of Tibet Autonomous Region, the railway represents a triumph of engineering over extreme geographical and climatic challenges. The project, initiated in 2001, was designed to connect the remote and mountainous Tibetan Plateau with the rest of China's rail network, fostering economic development and cultural exchange in one of the world's most isolated regions. The Qinghai–Tibet Railway is renowned for its innovative solutions to the logistical and environmental hurdles posed by the harsh terrain. Nearly half of the railway is located at altitudes above 4,000 meters (13,123 feet), earning it the nickname 'the Roof of the World Railway.' At its highest point, the Tanggula Pass, the track reaches an altitude of 5,072 meters (16,640 feet), making it the highest railway in the world. Specially designed trains were equipped with oxygen supply systems to prevent altitude sickness for passengers, a necessity in such a thin-air environment. Additionally, engineers implemented advanced permafrost stabilization technology to ensure the railway’s stability across the frozen ground, which could thaw and refreeze seasonally. The inaugural train journey was a moment of national pride, attended by Chinese officials and broadcast widely across the country. The railway played a pivotal role in China's broader strategy to integrate Tibet into its economic and political framework. While the project was hailed as a modern marvel, it also sparked controversy, with critics raising concerns about its environmental impact and its implications for Tibetan culture and autonomy. Today, the Qinghai–Tibet Railway continues to be a vital link in the region, transporting passengers and goods across some of the world's most challenging terrain. Its success has inspired other high-altitude rail projects around the globe, further cementing its legacy as a groundbreaking achievement in railway engineering.