Much of southern Jiangxi, once cut off from the outside world by rugged mountains, is far more connected. High-speed rail links it with the city of Shenzhen, the country"s economic powerhouse close to Hong Kong. Expressways also reach every county, and paved roads now extend into villages.

　　For local business owners, it no longer means spending two days and two nights on the road to source a critical part. Now they can hop on a high-speed train, pick up what they need in the morning and return that afternoon, drastically speeding up the development of a prototype.

　　The change is not only about getting around. Industries such as non-ferrous metals and advanced materials, electronics and information technology, and textiles and apparel have taken root here. For ordinary people, the changes are closer to home. Housing has improved, drinking water is safer, and schools and medical care are more accessible.

　　More people can now earn a living without leaving their hometowns. In March, the Hong Kong Polytechnic University launched a facility dedicated to research into smart wearables and smart clothing in Xingguo, a county next to Yudu.

　　This summer, Yudu welcomed students from more than 170 universities across China who came to retrace the Long March at the places where it began. Many realized that the Red Army soldiers who set out were their age.

　　"Standing where those young soldiers began their journey gave me a deeper understanding of what they accomplished," said Liu Fanshuo, an undergraduate studying automation.

　　Today, five modern bridges span the Yudu River near the crossings where local people once built pontoon bridges to help the Red Army cross.

　　On the banks, Sun pours hot tea for tourists whose lives might have been very different had those soldiers never crossed.

　　(Web editor: Zhang Kaiwei, Zhong Wenxing)