Lake Hillier sits on a remote island off Western Australia. For 200 years, it stayed bubblegum pink through every season. Algae and bacteria in the salt crust cause the color, not the water. It is safe to swim in, just not to drink. Bottle a sample and it keeps that same shade. Heavy rain in 2022 diluted the salt, turning the lake grey. Scientists expect the pink to return within a decade.
