Sumner Bar.

Sumner Bar sits at the mouth of the Avon and Heathcote Rivers where sand banks shift with each flood cycle, producing hollow, fast A-frame peaks when conditions align. It needs a solid SE swell to wrap into the estuary on a low incoming tide - when it happens the lefts stack up in clean lines, but those days are genuinely rare. The wave is steep with vertical takeoffs and barrel sections on the better ones, though flat spots interrupt longer rides. Sheltered from prevailing southwesterlies by the Clifton headland, the bar lights up during winter storms when most Canterbury breaks are blown out. Word travels fast when it turns on, yet the fickle nature keeps crowds manageable - you will share it with the locals who watch it daily. Strong rips run through the estuary channel and white shark sightings occur in the area, so situational awareness matters. A sand-dependent right can also peel off the point at the end of Sumner Beach on bigger swells. Check from Cave Rock or Clifton Hill for the best vantage before paddling out.

Hollow A-frames stack when the Avon flood shifts sand banks into rare alignment.