Lake Teletskoye

Lake Teletskoye (Russian: Озеро Телецкое, Altay: Алтын Кӧл, Altyn-Köl, literally: "Golden Lake") is the largest lake in the Altay Mountains and the Altai Republic, Russia, and has a depth of up to 325 meters.

Situated at a height of 434 m (1,424 ft) above sea level, the lake is 78 km (48 mi) long and 5 km (3.1 mi) wide and lies between the mountain ridges Korbu and Al-tyntu, on the junction of Sailughem Mountains and Western Sayans. Its surface area is 233 km2 (90 sq mi); however, due to its considerable depth (325 m, 1,066 ft), the lake contains no less than 40 km³ (9.6 cubic miles) of fresh water. Annual water level fluctuations are estimated at some 348 sm. The lake transparency is high, with the visibility of the lake water ranging from six to fourteen meters.

About 70 rivers and 150 temporary streams flow into the lake, the largest of them, Chulyshman River, supplying more than half of the lake's water. The lake is drained through a single outlet, the Biya River, which, after its confluence with the Katun River, forms one of Siberia's largest rivers, the Ob River.

The lake is surrounded by mountains of 600-1,300 m in the northern part and about 1,700-2,400 m (5,600 - 7,900 ft) in the southern part. Lake Teletskoe is included into Altaisky Nature Reserve. That reserve along with the Katun Natural Reserve and the Ukok Plateau Nature Refuge were listed as one of UNESCO World Natural Heritage Sites under the name "Golden Mountains of Altai".

The Altay people have a legend about the name of the lake in their language, which means Golden Lake. According to this story, once, a rich man had a ingot of gold, which he wanted to use to buy food. He travelled around Altai, but could not find anyone who would sell him any food. Eventually, he threw the gold into the lake. This legend is the origin of the name.