Just as everywhere in the world, natural conditions have influenced the development of transport routes on the Karelian Isthmus. Before the 20th century, machines were not used in civil engineering – everything had to be done by manual labour. Because of this, roads were made over easy terrain, for example, over ridges. In the earlier centuries, travelling and goods transporting along waterways had been the easiest solution. However, construction of the Saimaa Canal became possible only after certain technological developments in the 19th century.