Manuka Bay Track
From Hurunui River Mouth, veer left opposite the entrance to the campground. The short metal road takes you up to the top of a cliff to a viewpoint and the start of the Manuka Bay Track. Unless you happened to look closely at the Topo Map, you wouldn’t even know there is a track, and it is worth spending some time on it. It follows the cliff, then swings down to the lagoon, back along the cliff, past the actual Hurunui River mouth, and finally into Manuka Bay. You can walk all the way round to Gore Bay as an extension.
The best feature is the view over the lagoon, which was completely unexpected.