Trestle bridge-192

Timber trestle bridges were extensively used in the 19th century, from 1 to 3 per cent of the total length of the average railroad.
Many timber trestles were built in the 19th and early 20th centuries with the expectation that they would be temporary. Timber trestles were used to get the railroad to its destination. Once the railroad was running, it was used to transport the material to replace trestles with more permanent works.