A deep dive followed by a nice wall awaits you off the shore by seagrapes resort and lands end resort. You can follow this site down down to the depths that your training and gear will allow. For sport diving take it no more than 34m to be safe and enjoy the formation that makes for the 'hole'.
The hole is almost a tunnel that exits the wall at 100ft. Enjoy the sensation and make sure you have good buoyancy as you can get sucked down as your bcd gets crushed by the pressure here. It's a nice feeling all the same and quickly time to start ascending into the other part of the dive caverns and reef.

This video shows the divers arriving at the wall exit and the triangle hole shape suddenly appears.

Another hole in the wall dive video here from eli fuller.