What is a mermaid mirror? Technically , it's when bubbles interact with the cave walls or crevices, they can create a shimmering, reflective effect, especially when the water is calm and clear. We find them a lot in caves and swim throughs. We call them mermaid mirrors because we can often see our reflection, especially if the water is super calm... So it feels a little magical. UPDATE: I posted the follow-upโswim through the mirror cave with me + learn how it formed. Itโs pinned on my page! . #ocean #mermaid #mirror #reflection #beauty #cave #freediver #freediving #oahu #hawaii #fyp #travel #dive #freedivinggirl