Natural attractions of Issyk Gorge.

"The waters of Lake Issyk are filtered in large quantities through the dam and the lake bed itself. This filtration often exceeds the inflow of water into the lake from the Issyk River. This uneven flow of water into the lake creates very sharp fluctuations in its level. Upstream, in the area of ​​the uppermost sections of the spruce forest, lies a third lake, Bozkul."

"Nature of Kazakhstan in Essays and Pictures." N.N. Palgov. 1950.

Moraine lakes in upper reaches of Issyk River.

Among the environs of Almaty, Lake Issyk is a favorite excursion destination. It lies in the valley of the Issyk River, which flows along the northern slope of the Zailiskiy Alatau mountain range and emerges from the mountains onto a plain 40 km east of the city.
From the mountain exit, where the large village of Issyk is located, it's another 11 km to the lake. This final stretch of the journey can be reached by car as far as the lake's dam. From here, the ascent must be made either on foot or on horseback.
At an altitude of 200 meters from the foot of the dam lies the Small Issyk Lake, or Round Lake. This lake has a perfect oval shape. In summer, its level rises 3-4 meters above normal, and then the water gushes out through narrow rocky gates and cascades down the slope of the dam in a turbulent, foaming waterfall.
Half a kilometer further up the dam, at an altitude of 1,700 m. a. s. l., lies the Big Issyk Lake. In summer, the excess waters form a second (upper) waterfall, rushing toward the Small Lake. By autumn, both waterfalls cease to exist. Situated among felsic porphyry, the lake is distinguished by its particular beauty.
Mountain peaks rise up to a thousand meters above the lake. Among them, it appears like a greenish-blue fragment of a mountain, decorated with dense forest groves. Rocky mountain outcrops extend far into the lake's waters, forming picturesque bays and coves between them.
Most researchers attribute the formation of Lake Issyk to a rockfall that dammed the valley. Some researchers also believe that moraine deposits brought there by an ancient glacier may also be present at the beginning of the dam. In winter, the lake's water is quite transparent; the secca circle (a secca is a device for measuring water transparency) can be visible at a depth of 13 meters.
But in summer, due to the turbidity of suspended silt particles carried by the river, the water's transparency drops to 2.5 and even 1.5 meters. Large quantities of Lake Issyk filter through the dam and the lake bed. This filtration often exceeds the influx of water from the Issyk River.
This uneven flow of water into the lake creates very sharp fluctuations in its water level. Upstream, in the area of ​​the uppermost spruce forest, lies a third lake, Bozkul. It is backed by a high embankment of ancient glacial deposits consisting of rock and rubble.
The entire embankment and adjacent mountain slopes are covered with Schrenk spruce and shrubs. A modern glacier, entirely encased in a mantle of rock debris, approaches it from the left side gorge. Lake Bozkul is empty. Its gray sandy bottom is cut by several channels of the inflowing stream from the Kassin Glacier.
The waters of this stream seep into the sandy bottom and continue on as underground drainage. At the foot of the Bozkul Dam, they and other streams that have joined them emerge. But when the Kassin Glacier melts especially intensely, the stream covers the bottom of Bozkul with a thin layer of water for several hours (from evening until morning).
Beyond Lake Bozkul, the forest soon ends. Subsequently, the river valley is once again blocked by a stone dam, formed by an ancient glacier and rock falls. This final dam impounds the river's fourth lake, called Akkul (White Lake). This lake lies in the alpine meadow belt at an altitude of 3,100 m. a. s. l.
The bare mountain slopes surrounding the lake are covered in dark scree. This gives it a gloomy and austere appearance. Its green, murky waters have no clear outlet. They flow out of the lake somewhere beneath the stones of the dam, making their presence known in places with a faint murmur emanating from within.
From the Akkul Dam, some glaciers lying in the very upper reaches of the Issyk River are visible. They have all been explored and named. One of them (the easternmost) with a massive rock (nunatak) on its left bank is the Palgov Glacier. To the west of it is the wide, semi-basin Academician Grigoriev Glacier, and beyond it are the Mezhduyetsny, Dvukhlopastny, Kokbulak, and Lobasty glaciers.
At the rock-covered end of the Grigoriev Glacier, a small moraine lake glistens greenly, the fifth in the Issyk River valley. It is located below the mountain sections where glacial streams are born. The majestic panorama of the river's upper reaches is capped by the snow-covered, flat ridges of the main ridge.
On a clear, sunny day, they sparkle like well-cleaned enamel; during windy and cloudy weather, the whitish dust of a snowstorm hovers above them.

Authority:
"Nature of Kazakhstan in Essays and Pictures." N.N. Palgov. Publishing House of Academy of Sciences of Kazakh SSR. Alma-Ata. 1950.