Lake Hillier is a saltwater lake barely a third of a mile long, tucked away on Middle Island off the southern coast of Western Australia.
For more than two centuries, it was famous for one thing above all: its bubblegum-pink color, which held steady regardless of the light or time of day, and stayed just as vivid even when scooped into a glass.
All of that ended in 2022, when an episode of extreme rainfall linked to climate change diluted the lake’s salinity and the water shifted from vibrant pink to a bluish gray.
It hasn’t fully regained its original color since. Experts in the Esperance region say it should gradually return as evaporation concentrates the salt again — a process they estimate will take between five and ten years — though they caution that another extreme downpour could delay the recovery.
The British explorer Matthew Flinders first documented the lake in January 1802, when he climbed to the island’s highest point and noted a small rose-colored lake in his journal.
He named it in honor of William Hillier, a crew member who had died of dysentery shortly before. The crew found the water as salty as the Dead Sea and took the opportunity to load salt onto their ship.
The Science Behind the Color
The lake lies within the Recherche Archipelago Nature Reserve and has a salt concentration of nearly 28 percent — roughly eight times that of the ocean. Only extremophiles can survive in it.
In 2015, a team from the Extreme Microbiome Project collected water and sediment samples and identified around ten species of salt-loving bacteria and archaea, along with several varieties of the alga Dunaliella salina.
A more recent genetic study, published in 2022, expanded that count to hundreds of distinct microorganisms coexisting in the lake.
Most of those microbes are naturally pink, reddish, or orange. The reason comes down to survival: to protect themselves from solar radiation and the extreme salt concentration, they produce pigments known as carotenoids — the same compounds that give a carrot or a flamingo its color.
With millions of these microorganisms packed into a relatively small body of water, that pigment is enough to color the whole lake.
How to Get There and What to Expect
Lake Hillier has no tourist facilities and no access by land.
The nearest town is Esperance, a coastal community roughly 80 nautical miles by sea from the lake, with no road connecting to Middle Island. That leaves two ways to reach it: by air or by sea.
The most common option is a scenic flight. Goldfields Air Services, operating under the name Fly Esperance, departs from Esperance Airport on flights of about an hour and forty minutes that pass over Middle Island as well as Cape Le Grand National Park and Lucky Bay, known for having some of the whitest sand in Australia.
Prices run around 425 Australian dollars per person; the flight requires a minimum of two passengers to operate, and there are usually several departures a day.
In season, between December and April, helicopter flights also operate out of Esperance — a more flexible option, though just as weather-dependent: strong winds can ground a flight without warning.
The second option is by sea. Local operators such as Esperance Island Cruises run boat trips to the island, roughly six hours round trip, though these are offered far less frequently than flights and are generally booked as private charters.
Middle Island has one other curious claim to fame beyond the lake: it was the hideout of Black Jack Anderson, the only documented pirate in Australian history, who was active across the Recherche Archipelago in the early 1800s.
Can You Swim in the Lake?
Technically, yes. The extreme salt concentration makes your body float with almost no effort, and the microorganisms responsible for the color pose no risk to skin or health. In practice, however, swimming is not permitted.
Middle Island falls within a nature reserve protected by the Western Australia Department of Parks and Wildlife.
Access on foot and direct contact with the water are reserved almost exclusively for scientific expeditions with special permits — both to protect the ecosystem and to avoid interfering with ongoing research into the lake’s recovery following the 2022 event.
For the vast majority of visitors, the experience means viewing the lake from the air — or, on boat trips, from the water without going ashore. It is, in that sense, a destination meant to be seen rather than touched.
