the answer is steel
There are many different lengths of suspension bridges.
Steel, light weight, stainless, sturdy, it will not rust and the lead to civilians dropping onto the tracks, or worse into the path of a train.
Their building material was mud.
The initial popularity of the truss bridge was based primarily on its simplicity of construction and economics of building the bridges. In the 1800s, wood was cheap and plentiful. Wood was an ideal construction material because it was flexible and elastic to some degree and could withstand the variety of forces that acted against it. The early truss bridges were built from wooden timbers and were constructed in trestle forms where they were composed of a braced framework of timbers, piles or steel beams built to carry roads or railroads over a depression in the landscape topography.
False
Janet Kardon has written: 'Machineworks' 'Siah Armajani - Bridges - Houses - Communual Spaces - Dictionary for Building' '1967 At the Crossroads March 13 April 26, 1987' 'The Ideal Home, 1900-1920'
A material with a density of 0.2 g/ml is light, suitable for cushions in a couch since it provides softness without adding too much weight. However, it wouldn't be ideal for building a bridge due to its low mass and potential inability to support structural requirements.
Mesh is an ideal material to use that is durable.
In my opinion silk.
Since bridges were expensive to build, there were not very many of them. The result was that roads tended to converge on bridges. This concentrated traffic, and this, in turn, made the bridge an ideal spot to set up an inn, food stalls, a fair, and eventually, a town.
The ideal thickness for a concrete slab when building a house is typically 4 inches to 6 inches. This thickness provides a strong and durable foundation for the structure.
cause its cheap