Ertso Lake

Ertso Lake: The Ghost Lake of the Karst Plateau

In the annals of Georgian geography, few places hold as much mystery as Ertso Lake. Located in the historic Ertso-Tsona basin (currently in the occupied territory of South Ossetia), it was once the country’s largest karst lake. Its fame, however, came from its most peculiar characteristic: the lake would periodically vanish. The water would drain away completely into a subterranean network of karst caves and channels, leaving behind a vast, grassy depression, only to reappear months or years later. This incredible natural phenomenon made Ertso a place of legend. Today, the legend is all that remains. Since the early 1990s, the lake has remained in its drained state, a vast, empty basin where a great body of water once lay. Its story is now a poignant tale of a lost natural wonder, a “ghost lake” that lives on in memory and geographical textbooks, currently inaccessible to visitors.

Identification and Location

• Name: Ertso Lake (ერწოს ტბა).
• Location:
  • Country: Georgia
  • Region: Shida Kartli (in the occupied territory of South Ossetia)
  • Municipality: Java
• Nearest Major Landmark/Area: Located in the Ertso-Tsona basin, a large karst plateau.
• Coordinates: Approximately 42.4150° N, 43.8300° E.

Physical Characteristics

• Surface Area: Formerly up to 0.41 square kilometers, now effectively zero.
• Maximum Depth: Formerly up to 19 meters.
• Elevation Above Sea Level: Approximately 1710 meters.
• Water Source(s): Formerly fed by precipitation and springs.
• Outflowing Stream(s): Water drained through underground karst channels.
• Water Type: Freshwater.
• Geology of Basin: Karst depression (polje).

Ecological Information

• Flora: The former lakebed is now a meadow, covered with grasses and marshland vegetation.
• Fauna: When it held water, it contained fish.
• Unique Ecological Features: Its former status as a large, periodically disappearing (intermittent) karst lake was its defining feature.
• Conservation Status: Located in an occupied territory, its status is undetermined.

Human Interaction and Significance

• Historical Significance: A famous and unique geographical feature of Georgia, widely studied by geographers. It was a place of local legends.
• Current Use: The area is used for grazing by the few remaining locals. It is not accessible for tourism.
• Environmental Issues: The primary issue is the complete disappearance of the lake ecosystem.

Interesting or Unique Facts

• It was the largest karst lake in Georgia before it disappeared.
• The phenomenon of the lake vanishing and reappearing was a major subject of scientific study and local folklore.
• The lake has not refilled since the early 1990s, making it a “lost” natural monument.