 Economic growth and development in Western Australia 's northern regions in the 1940s prompted the state to quadruple road funding between 1946 and 1952 . Two " gangs " of workers were allocated to a 900 @-@ mile ( 1 @,@ 400 km ) length of North West Coastal Highway . Given the vast distance the highway travelled , and destructive cyclones in the Pilbara and Gascoyne that could destroy multiple weeks worth of work , the overall improvement was relatively insignificant . Over time , though , the road was improved . 
