Lake Retba

Lake Retba lies roughly 35 kilometres northeast of Dakar, separated from the Atlantic Ocean by a narrow strip of coastal dunes, and it earns its alternative name, Lac Rose, from a microorganism that proliferates in its hypersaline water and produces a vivid pink pigment. The Dunaliella salina algae thrives in water with salt concentrations approaching 40 percent by weight, and the beta-carotene it generates as a protective mechanism creates the lake's characteristic rose-pink colour, visible from the air and from the surrounding dunes.

The colour is most intense during the dry season from November to June, when strong sunlight and high evaporation rates concentrate the salinity and trigger maximum algae production. Local salt harvesters spend hours standing waist-deep in the pink water, raking crystallised salt from the surface onto wooden rafts before ferrying it to the shore. The work is physically demanding, conducted in full sun with no protective equipment, and the salt industry at Lac Retba has operated on the same basis for generations.

The pink hue varies from pale rose to deep magenta depending on the time of day, the season and recent rainfall. In the early morning and late afternoon the colour is most saturated; after heavy rain the freshwater inflow dilutes the salinity and the lake can lose its pink character for days or weeks. The September 2022 floods temporarily stripped the lake of its colour and disrupted salt harvesting, though the pink had substantially returned by 2025, demonstrating the resilience of the Dunaliella population.

Visitors can walk along the lake's eastern shore where informal markets sell salt harvested that morning, and local guides offer short boat trips to the centre of the lake where the colour appears most vivid. The strip of dunes separating the lake from the ocean supports small fishing communities, and the area between the lake and Dakar's suburbs retains a genuinely local character despite its proximity to the capital.

Tour operators commonly combine a visit to Lac Retba with Île de Gorée, as both lie within an hour's drive of central Dakar and represent contrasting but equally vivid experiences of Senegal: one defined by history and the contemplation of atrocity, the other by a living natural process that has few parallels in West Africa. The lake is at its most spectacular from the air, and small aircraft offering scenic flights over the Dakar peninsula sometimes route over Lac Retba on request.

It is one of the few naturally pink lakes in the world, a phenomenon caused by a specific combination of salinity, sunlight and a harmless algae that is unique to highly saline environments.

The salt-harvesting tradition at Lac Retba offers a window into a form of subsistence labour that has survived largely unchanged for generations.

Its proximity to Dakar makes it an accessible half-day trip that can be combined with Île de Gorée or the beaches of the Petite Côte.