Ulaanbaatar is the capital of Mongolia and is widely recognised as the world's coldest national capital. Its severe winter climate results from high elevation, inland location and exposure to cold Siberian air.
The city lies in the Tuul River valley at roughly 1,350 metres above sea level. Winters are long and dry, and January average temperatures remain far below freezing. Summer is short but can be warm, producing a sharply continental climate.
Ulaanbaatar developed around a mobile Buddhist monastic settlement that moved locations several times before settling at its present site in 1778. Its name means “Red Hero,” adopted in 1924 after Mongolia became a socialist republic.
Astana is also famous for extreme winter cold, but it is the capital of Kazakhstan, not Mongolia. Ulaanbaatar is Mongolia's political, economic and cultural centre and contains a large share of the country's population.