Namdang Stone Bridge, Stone bridge in Sibsagar, India.

Namdang Stone Bridge is a slightly curved stone arch bridge over the Namdang river near Sibsagar, Assam. It measures 60 m long, 6.5 m wide and 1.7 m high, with six culverts letting the water pass beneath. Much of the structure was cut from a single massive rock, and carved sculptural panels decorate the arches. National Highway 37 now runs across it, linking Sibsagar with Jorhat and districts to the west.

The bridge was built in 1703 under Ahom king Rudra Singha and served as the western entry point to the military capital of Rangpur. At the time of its construction, it was one of the most important infrastructure works in the region.

The bridge was built by Bengali stonemasons who came specifically to Assam for this project. The care in how the stone was shaped and joined is still visible to anyone who walks across it today.

The bridge carries National Highway 37, so traffic crosses it and there is no separate pedestrian lane; walkers share the roadway with vehicles. It stands a few kilometres from Sibsagar town on the road toward Jorhat. Six culverts channel the Namdang beneath the deck, and the low 1.7 m parapet allows a view of the carved arch panels from the roadside.

The bridge was carved from a single solid block of stone, which is a very rare technique for a structure of this age. This kind of one-piece construction is almost never seen in other bridges across the region.