Puente Bolivar is a 488 meter long iron viaduct. Most of the viaduct is composed of four legged towers with little deck truss spans between the towers. A long span over the Rio Chili looks very much like a Fink truss, which was designed by Albert Fink of Germany in the 1860's according to the excellent Wikipedia entry on truss bridges.
In this type of truss, we can see diagonal tension members being used to support vertical elements at the eighth points of the span. I like how we can clearly see the forces being carried on this type of truss.
At the time it was built, I believe this bridge was used to carry a railroad on it's way to Cuzco. Now its used to carry a single lane of vehicles west into the city. We'll take another look at this interesting structure tomorrow.
Peru's Bridges: Puente Bolivar (1) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.