SH 1 is long, in the North Island and in the South Island. For the majority of its length it is a two-lane single carriageway, with at-grade intersections and property accesses, in both rural and urban areas. These sections have some passing lanes. Around of SH 1 is of motorway or expressway standard : in the North Island and in the South Island. Current road construction will see an extra in the North Island and in the South Island upgraded to motorway or expressway standard by 2022.