Ulan-Ude (Russian: Ула́н-Удэ́; Buryat: Улаан-Үдэ), formerly Verkhneudinsk (Верхнеу́динск), the capital city of the Buryat Republic, Russia, is located about 100 km south-east of Lake Baikal. It sits at the foot of the Khamar-Daban and Khrebet Ulan-Burgasy mountain ranges, next to the confluence of the Selenga River and its tributary, the Uda. The city is divided into two parts by the Uda. It is the third largest city in East Siberia. It is served by Ulan-Ude Airport (Mukhino) as well as the smaller Ulan-Ude Vostochny Airport. Ulan-Ude was founded in 1666 by the Russian Cossacks. Due to its geographical position, the city grew rapidly and became a large trade centre which connected Russia with China and Mongolia. There are old merchants' mansions richly decorated with wood and stone carving in the historical center of Ulan-Ude, along the river banks. They represent beautiful examples of Russian classicism. There is also a large and highly unusual head of Lenin in the central square.