In local surf lore this area is called "China Wall". Like many other surf spots first popularized by local surfers the names given to the surfing areas sometimes had no relationship to anything familiar. There is no wall like structure just huge rocks flanking a dangerous, sweet surfing spot.
"China wall" is on the eastern shore and is a very dangerous place for the amateur surfer. A number of tourists drawn by the mystique of the name have died there.
Here's a description of surfing in the China Wall area (Portlock) from a local surfer posted on my web site along with mypicture below:
"Portlock..steeped cliff sdie walk down to the flats and you are watching surfers drop into a realm you will never bwe able to define to friends. Not evn your narration with evidence of picture perfect left breaking wave over the ledge will help you. How the Heavens have blessed myself the opprtunity to drop intop the face of the fast approaching peak slide next to the head high lava rock formation, if you fall you may die form head injuries, its live or die, no bravado iniside simkply the confidence knowing 'I WILL LIVE, I WILL MAKE THE DROP'. Release the rail slide like the seagull and within 2 seconds around the point (left turn @55 degrees), then upright to lean again right 45degrees to slide further inside to the speeddy shallows. Gods only knows no business transaction, no material score will ever touch my heart like Portlock. The only place that renders the entir world in last place or perhaps obsolete"