Lake Afrera is a hypersaline lake

Hypersaline lake

A hypersaline lake is a landlocked body of water that contains significant concentrations of sodium chloride or other mineral salts, with saline levels surpassing that of ocean water . Specific microbial and crustacean species thrive in these high salinity environments that are otherwise...

 in northern Ethiopia

Ethiopia

Ethiopia , officially known as the Federal Democratic Republic of Ethiopia, is a country located in the Horn of Africa. It is the second-most populous nation in Africa, with over 82 million inhabitants, and the tenth-largest by area, occupying 1,100,000 km2...

. Located in Administrative Zone 2

Administrative Zone 2 (Afar)

Administrative Zone 2 is one of five Zones of the Afar Region of Ethiopia. This zone is bordered on the south by Administrative Zone 4, on the southwest by Administrative Zone 1, on the west by the Amhara Region, and on the northeast by Eritrea. The administrative center of Zone 2 is Abala...

 of the Afar Region

Afar Region

Afar is one of the nine ethnic divisions of Ethiopia, and is the homeland of the Afar people. Formerly known as Region 2, its current capital is Asayita; a new capital named Semera on the paved Awash - Asseb highway is under construction....

, it is one of the lakes of the Danakil Depression

Danakil Depression

The Danakil Depression is a desert basin which lies in the Danakil Desert in north-eastern Ethiopia and southern Eritrea. It belongs to the homeland of the Afar people. It lies up to 100 m below sea level as a result of tectonic activity caused by plate movements...

. According to its entry in Lakenet, it has a surface area of 100 square kilometre, although another source states the area is 12,500 hectares. An unconfirmed report gives its depth as 160 m (525 ft); the lake is fed by underground streams.

It is also known as Lake Giulietti, the name Raimondo Franchetti

Raimondo Franchetti

Baron Raimondo Franchetti has been the name of more than one Italian Baron, the most famous of whom lived from 1889 until his death in an airplane crash in the Egyptian desert in 1935.-Family:...

 bequeathed it, after the Italian

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

 explorer Giuseppe Maria Giulietti

Giuseppe Maria Giulietti

Giuseppe Maria Giulietti was an Italian soldier, geographer and explorer. He was born in a wealthy family in Casteggio, province of Pavia....

 who was slain by Afars

Afar people

The Afar , also known as the Danakil, are an ethnic group in the Horn of Africa. They primarily live in the Afar Region of Ethiopia and in northern Djibouti, although some also inhabit the southern point of Eritrea.-Early history:...

 southwest of the lake. Another name for this body of water is Lake Egogi (or Egogi Bad), which is the name L.M. Nesbitt's Afar guide gave it when the British explorer became the first European to see it in 1928.

The single island in Lake Afrera, Franchetti Island (also known as "Deset"), located in the southern part of the lake, is considered the lowest-lying island in the world.

Unlike other saline lakes in Ethiopia (e.g., Lakes Abijatta

Lake Abijatta

Lake Abijata lies in Ethiopia south of Addis Ababa, in the Abijatta-Shalla National Park. According to the Statistical Abstract of Ethiopia for 1967/68, the lake is 17 kilometers long and 15 km wide, with a surface area of 205 square kilometers...

, Shala

Lake Shala

Lake Shala lies in Ethiopia south of Addis Ababa, in the Abijatta-Shalla National Park. The lake is 28 kilometers long and 12 wide, with a surface area of 329 square kilometers. It has a maximum depth of 266 meters and is at an elevation of 1,558 meters...

, and Chitu), the pH of Lake Afrera is low and in the acidic range. Although little studied, a few species of fish are hosted by Lake Afrera, including two endemics: Danakilia franchettii

Danakilia franchettii

Danakilia franchettii is a species of cichlid fish from the saline Lake Giulietti and nearby swamps in Ethiopia. It was the only member of the genus Danakilia until the description of D. dinicolai in 2010....

(a cichlid

Cichlid

Cichlids are fishes from the family Cichlidae in the order Perciformes. Cichlids are members of a group known as the Labroidei along with the wrasses , damselfish , and surfperches . This family is both large and diverse. At least 1,300 species have been scientifically described, making it one of...

) and Lebias stiassnyae (a pupfish

Pupfish

Pupfish are a group of small killifish belonging to ten genera of the family Cyprinodontidae of ray-finned fish. All pupfish are especially noted for being found in extreme and isolated situations, in various parts of North America, South America, and the Caribbean region...

).

Salt extraction

Rock salt has been mined at Lake Afrera, and the surrounding part of the Afar Depression, for centuries. Lt. Lefebvre recorded some of the hazards of mining salt from the Depression, which he heard from one of the miners himself:

He said that this lake often changes its shape and place, which he expressed in these terms: the lake moves. Often, he added, on going to a place which the evening before was quite solid, you suddenly break through, and disappear in the abyss. But what is more frightful is the overflow of the waters: sometimes the lake rises like a mountain, and falls again into the plain like a deluge; entire caravans, men and beasts are engulphed. There are, however, precursory signs, of which mounted men only can take advantage, by flying at the utmost speed of the animals; occasionally some of them have thus escaped, and it is from them these terrible details are procured.

More recently, the Ethiopian Mineral Resources Development Enterprise has established the existence of 290 million tons of salt at Lake Afrera alone. Some local companies used to produce salt from the lake by pumping the brine

Brine

Brine is water, saturated or nearly saturated with salt .Brine is used to preserve vegetables, fruit, fish, and meat, in a process known as brining . Brine is also commonly used to age Halloumi and Feta cheeses, or for pickling foodstuffs, as a means of preserving them...

 into artificial ponds for evaporation and subsequent precipitation.

Following the 2011 eruption of Nabro, the lake is contaminated with sulphuric acid, making the salt inedible