Puente ferroviario Biobío en Coihue, Railway bridge across Biobío River between Los Ángeles and Negrete, Chile.

The Biobío Railway Bridge connects Los Ángeles and Negrete across the river with a span of approximately 500 meters. It stands on concrete-filled iron pillars arranged at regular intervals to cross the water.

The Dirección de Obras Públicas ordered the bridge to replace provisional crossings, with plans by engineer Enrique Budge Prats approved in late 1888. The Chilean firm Lever, Murphy y Compañía of Valparaíso won the 1889 tender over a US syndicate and built it in 1890. In 1931 the beams were suspended by a parabolic chain anchored to the abutments, and around 1947 the lattice was changed to a Warren type.

The bridge represents a crucial connection in Chile's Southern Railway Network, linking the stations of Santa Fe and Coihue for regional transportation.

The bridge is reached near the Coihue locality, between the Los Ángeles and Negrete communes, and carries the EFE Red Sur line between the Santa Fe and Coihue stations. The rail deck sits 10 to 14 metres above the river, a height that depends on the river's flow rather than the season. The tubular piers are sunk about 12 metres below the riverbed.

The bridge was not rebuilt: its lattice girders were reinforced in 1931 with a parabolic chain anchored to the abutments, and around 1947 the lattice was changed to a Warren type. The original structure weighed about 1,100 tonnes of iron.