The saltiest water on Earth is Don Juan Pond in Antarctica. It has a salt content of 44 percent. By contrast, the world's oceans average about 3.5 percent salt content.
The water in Don Juan Pond is so salty that it remains liquid even at the temperature of minus 22 degrees Fahrenheit. It is located 83 miles west of U.S.-operated McMurdo Station in Victoria Land in eastern Antarctica.
The second saltiest water on Earth is Lake Vanda in Antarctica. Lake Vanda is located only 3.3 miles from Don Juan Pond.
Lake Assal in Djibouti, Africa, is the third saltiest body of water on Earth. Lake Assal has a salt content of 34.8 percent.
According to researchers at Brown University, Don Juan Pond gets its salt when nearby salt-parched soil sucks salt out of the atmosphere. Enough fresh water flows in to keep the pond liquid. These researchers say it's possible ponds like Don Juan Pond could exist on Mars.