Jellyfish Lake is a shadowed oasis hidden among the mushroom-like Rock Islands of Palau. This forest‑fringed saltwater lake invites visitors to float with millions of gentle, stingless jellyfish that glow like drifting amber clouds under emerald light. The lake formed about 12,000 years ago, when rising seas flooded an ancient reef basin that was gradually cut off from the ocean. Over centuries, its jellyfish evolved in isolation, shedding their stings and multiplying without predators in sight.