An aerial drone photo taken on Oct. 24, 2026 shows the construction site at the Junlian tunnel of the Chongqing-Kunming high-speed railway on the border of southwest China"s Yunnan Province and southwest China"s Sichuan Province. The last pair of 500-meter-long steel rails was steadily placed on the track on Saturday, marking the official completion of track laying for the Chongqing-Kunming high-speed railway. (Xinhua/Hu Chao)

　　Workers lay tracks at the Junlian tunnel of the Chongqing-Kunming high-speed railway on the border of southwest China"s Yunnan Province and southwest China"s Sichuan Province, Oct. 24, 2026. The last pair of 500-meter-long steel rails was steadily placed on the track on Saturday, marking the official completion of track laying for the Chongqing-Kunming high-speed railway. (Xinhua/Hu Chao)

　　Workers lay tracks at the Junlian tunnel of the Chongqing-Kunming high-speed railway on the border of southwest China"s Yunnan Province and southwest China"s Sichuan Province, Oct. 24, 2026. The last pair of 500-meter-long steel rails was steadily placed on the track on Saturday, marking the official completion of track laying for the Chongqing-Kunming high-speed railway. (Xinhua/Hu Chao)

　　(Web editor: Xue Yanyan, Zhang Tianrui)