What is the “triangle” at Strawberry?

[kingfisher82]

I see a lot of posts regarding the triangle at Strawberry, especially in reference to catching kokes. Can someone explain the triangle to me? I see it referenced in a ton of posts so I assume I’m not asking for top secret information. I’ve fished the berry over 200 times, mostly targeting cutts and bows, but I still don’t know what the triangle is referencing.
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