Lake Sevan Day is observed in Armenia on every last Sunday of August, marking an important ecological observance established by the Ministry of Nature Protection of the Republic of Armenia in 1999. This day focuses on the preservation of Lake Sevan, the largest lake in the Caucasus and one of the world's largest freshwater high-altitude lakes, located in the Gegharkunik Province. The observance aims to address environmental issues such as water level reduction and increased eutrophication, which have negatively impacted the lake's ecological condition and biodiversity, including endemic species like the Sevan trout and the Armenian gull. Activities on Lake Sevan Day typically include shoreline clean-ups and other initiatives designed to improve the ecological conditions of the lake and its surrounding areas, coordinated by the employees of the Sevan National Park, which was created in 1978 to protect this vital natural resource.