Designed by a well known frenchman, Gustave Eiffel of tower fame, the Puente de Fierro (or Bolivar as it is sometimes called) was built in 1882 to be used as a viaduct for the train route to Cusco. At 488m long it was the longest in the world at the time, until some years later it was beaten by a Scottish bridge. Even today, not including suspension bridges, it is still the 7th longest bridge that exists.
The bridge crosses the river Chili in La Arboleda in southern Vallecito, a nice residential area. Photos are, as always, attached.