The Bori Tibetan Cantilever Bridge

The Bori Tibetan Cantilever Bridge

The Bori Tibetan Cantilever Bridge. The bridge spans the fast-flowing Yalong River, with a total length of 125 meters and a width of 3 meters. It is a single-arch bridge built using the principle of bracket arm relay and mortise-and-tenon construction. The bridge extends from both ends of the piers toward the center of the river, like two massive arms lifting the bridge deck. Therefore, people vividly call it the “Flying Bridge.”

Both piers are constructed from logs arranged in a crisscross pattern, interspersed with stone blocks, and built on the riverbank foundation. The layers of logs on the piers are bound together with “rope logs” to form a stable, unified structure. The massive piers support four thick logs that extend toward the river center, atop which more logs are stacked layer upon layer — five tiers in total — gradually reaching further into the river. Wooden planks are then laid on top to form the “Flying Bridge.” The piers are pointed and round in shape, with flood discharge channels left between the piers and the riverbanks. Above the piers are houses covered with slate tiles, resembling fortress-like structures. According to historical records, the Bori Tibetan Cantilever Bridge was first created in the 1840s by the outstanding Tibetan designer Tang Tongjibu. This bridge employs traditional Tibetan bridge-building techniques while incorporating the mechanical principles of bracket arms from Han Chinese architecture. The entire bridge is constructed entirely from wood and stone, without a single iron nail — truly a remarkable achievement in the history of bridge engineering in Tibetan regions.