Stephen tipped me off to something cool, in bridges! George Stephenson (the famous Rocket train engine of 1829) had a son, that designed bridges, for trains to cross rivers! That's cool!

 

It was built by the Hawks family from 5,050 tons of iron. George Hawks, Mayor of Gateshead, drove in the last key of the structure on 7 June 1849, and the bridge was officially opened by Queen Victoria later that year.

It was designed by Robert Stephenson to form a rail link towards Scotland for the developing English railway network; a carriageway for road vehicles and pedestrians was incorporated to generate additional revenue. The main structural elements are tied cast-iron arches.

 an all-masonry structure was ruled out because of the poor ground conditions in the river, so cast iron or wrought iron was inevitable for the superstructure

https://en.wikipedia.org/wiki/High_Level_Bridge,_River_Tyne