Lake Yalchik (Cyrillic: Яльчик, Jalčik) is the largest lake in Mari El, Russia, located in the Marii Chodra national park. Lake Yalchik plays a major role in tourism in region and several tourist centres are located here. It is renowned locally for its clean and warm water.
In fact, Lake Yalchik is a system of two lakes, the Greater and Smaller Yalchiks, which are linked by a channel which periodically dries up in summer. The elevation of Smaller Yalchik is higher than that of Greater Yalchik, but flow from Smaller Yalchik can only be observed at spring tide. The area of the lake is increasing due to the karst processes that shape the area. Legend says that the lake appeared after the major collapse of a meadow, which was originally in the location of the lake. The last major collapse occurred in 1914 and it generated a tsunami-like wave. At the bottom of the lake there are two series of karst caves, Шаблон:M to ft and Шаблон:M to ft long, and up to Шаблон:M to ft deep.
Greater Yalchik has a complex shape and many bays, whereas Smaller Yalchik has an elongated shape. Smaller Yalchik has two little brooks as inflows, but the Greater Yalchik has none.
The word Yalchik itself is a rendering of the Chuvash word Елчěк (Yälçek), which means a 'little village'. The village, which gave its name to the lake, was founded by the settlers from the modern Yalchiksky District of neighboring Chuvashia. Yalchik is an only major lake of the Marii Chodra, which name has Turkic roots, as the most of the lakes have the Mari names, and often have jär/yer endings, Mari for a lake.
Being popular for its unique nature, Yalchik attracts many tourists, mostly from Kazan. However, there are no beaches at the lake, and the most of its coastline is covered with reed. Many tourists reach Yalchik by own cars, but a significant number of them use a railway. The closest station to Yalchik is in the settlement of Yalchevsky.
Some Mari and Tatarstan universities sometimes arrange science conferences at the Yalchik's rest home.