At 11:00 on February 1, 2024, the world's largest span of stiff skeleton concrete arch bridge—Tian'e Longtan Grand Bridge in Nandan-Tian'e Expressway was completed and opened to traffic, which is the world's first arch bridge with a span of more than 600 meters.

It is understood that Tian'e Longtan Grand Bridge is a national transportation industry key science and technology projects, located in Tian'e County, Hechi, 6 kilometers upstream of Longtan Dam, across the Hongshui River, with a total length of 2,488.55 meters. The main bridge is a deck stiff skeleton concrete arch bridge with 600-meter calculated span, it also has bidirectional four-lane road and the designed travel speed is 100 km/h. In December 2020, construction of the main bridge project begun in full.

At the end of 2022, Nandan section to the Tian'e section of Nandan-Tian'e Expressway opened to traffic, the completion of the Tian'e Longtan Grand Bridge today will realize the fully open of Nandan — Tian'e Expressway through the whole line, the travel time from Pojie Township to Xiangyang Town was shortened from 2 hours to about 20 minutes, the travel time from Nandan County to the Xialao Township Tian'e County was shortened from three and a half hours to about an hour and a half, which will effectively open up the traffic "artery" of Guangdong and Guangxi Provinces, promoting the integration of Tian'e County into the Nanning 3-hour economic circle, Guiyang 2-hour economic circle, improving the transportation of agricultural and sideline products and the exchange of people along the route.