Lake Issyk

The Lake Issyk also known as Issyk Lake (, "Esik kóli") is a lake in Kazakhstan fed by the Issyk River. It should not be confused with the Issyk-Kul Lake in neighboring Kyrgyzstan.
History.
It is estimated that the lake was formed about 8-10 millennia ago, as a result of a catastrophic earthquake that caused the collapse of the right slope of the gorge. After the collapse, debris blocked the gorge and created a dam about 300 meters tall. A lake formed behind the dam, about 1,750 meters by 1,500 meters and a depth of 50 to 90 meters, at an altitude of 1,756 meters. Summer water temperatures do not exceed 8°C. The water was so transparent that on a sunny day you could see depths of as much as 10 meters. There are no fish in the lake.
The lake became known in Russia and Europe by the middle of the 19th Century, after the formation of the village of Nadezhdinskaya at the mouth of the gorge. Every explorer who visited these regions considered it his duty to visit the lake. One of the first researchers was the geographer Semenov Tien-Shansky, who mentioned the lake in his diaries: "we were delighted to see at our feet the "Green lake" (in Kazakh "Jasyl-Kol"), which had the purest and most transparent, thick bluish-green color of the TRANS-Baikal beryl. Beyond the lake rose a bold and steep jagged ridge of high squirrel ... this mountain the guide called Issyk-bash."
The Caspian tiger was found in the Issyk gorge and around the lake at least at the beginning of the 1900s and is mentioned in the diaries of Pyotr Semyonov-Tyan-Shansky.
The lake is mostly famous for the way it was created (an ancient natural landslide damming a valley), destroyed (another natural landslide destroying that dam in 1963, with a subsequent flood damaging the city of Esik), and re-created (with human help).