It is wholly single carriageway with two one-lane bridges at the Rakaia and Selwyn Rivers.

One set of traffic lights is found in Ashburton marking the southern terminus of the highway.

The highway begins as Bangor Road just west of Darfield town centre, and proceeds in a westerly directions towards the mountains through flat pastoral farmland.

The river here has carved out the surrounding land to form two level terraces.

The road emerges onto the plains but passes right underneath the towering Mount Hutt.