Lake Retba or Lac Rose lies north of the Cap Vert peninsula of Senegal, north east of Dakar. It is so named for its pink waters, caused by cyanobacteria in the water. The color is particularly visible during the dry season. The lake is also known for its high salt content, which, like that of the Dead Sea, allows people to float easily.
The lake also has a small salt collecting industry and is often the finishing point of the Dakar Rally.Many salt collectors work 6–7 hours a day in the lake, which has a salt content close to 40%. In order to protect their skin, they rub their skin with shea butter, produced from shea nuts obtained from the Shea nut tree, which is an emollient used to avoid tissue damage.
This lake was used on a task of the Amazing Race 6 in which teams had to collect salt in a basket from the bottom of the lake floor.This lake has a color from the large number of microorganisms and minerals.Local women spend up to 14 hours a day collecting there salt.The concentration of salt per liter of water about 380 grams.