Dongjin Bridge, Ancient pontoon bridge in Ganzhou, China.

Dongjin Bridge spans 400 meters across the Gong River, resting upon approximately 100 wooden boats connected by iron chains. The entire structure allows pedestrians to cross while adapting to changing water levels.

The bridge was first built between 1170 and 1173, when official Hong Mai promoted its construction. In 1224, prefect Zheng Xingzhi rebuilt it as a pontoon of boats linked by iron chains. It was rebuilt in 1506–1521 and again in 1933, destroyed in 1945 and 1949, and repaired on 29 August 1949; in 1990 its timber structure was replaced with steel.

Locals know the crossing as Jianchunmen Pontoon Bridge, after the city-wall gate it faces. Its other name, Huimin Bridge ("benefiting the people"), recalls its role as a free public crossing on the Gong River. The bridge is a protected provincial cultural relic.

The deck is 373 metres long and made of 17 linked sections, so expect a walk of several minutes over planks that sit directly on the boats. The surface shifts slightly underfoot and with the water level; the low edge rails are the only barrier, so watch children near the sides.

The structure is held together by traditional iron chains connecting the wooden boats, preserving ancient construction methods still visible today. This chain-connection method is rarely seen elsewhere and demonstrates how stable historical techniques can be.