Clarence River is located at the mouth of the Clarence River, just north of Kaikoura. The surf spot is accessible by driving for about 20 minutes north on State Highway 1. Just before reaching the river, you'll find some gravel and sand forestry tracks on the east side of the road, which will lead you out to the river mouth. Expect to do a bit of walking to get there, or you can make your way down the river bed.
The surf here typically offers a rivermouth wave that breaks to the right. It usually performs best on low to mid tides when the swell is coming from the southeast, but you'll also catch waves with easterly or southerly swells. The spot can handle swell sizes starting from about 2 feet (0.6 meters) and works best for expert surfers. The preferable wind direction is northwest, which can help shape up the waves nicely over the boulders that make up the river mouth. Just keep in mind that shifting bars and swell directions can affect where the peaks pop up along the shingle strand.
For those looking for a change of scene, Okiwi or Sandy Bay is nearby and is one of the few beach breaks in the area. It works better during lower tides with a southerly swell and offers offshore conditions when the northeast winds are blowing. It's a good spot to check out if Clarence River isn't firing at the moment.