Map showing average daily vehicular traffic on Portland's primary streets, in 1955. The map, which is from a report dated June 1955, shows only surface streets and the Harbor Drive expressway, because Portland did not have any fully-fledged freeways at this time. The first segment of the Banfield Freeway (I-84) opened in October 1955, and ran between 4nd Ave. and the city of Troutdale.