What is the capital of Mongolia?

Ulaanbaatar was for much of its history not a fixed city at all. It began as a movable monastic encampment that shifted location many times over the centuries, following the pattern of a nomadic society, before settling permanently on the Tuul River in the eighteenth century as a religious and trading centre on routes between Russia and China. It took its present name, meaning red hero, after the revolution of the 1920s brought a communist government, which then rebuilt it with Soviet-style planning and industry. The city holds an extraordinary share of the country's population, and its outskirts consist largely of districts of traditional felt tents connected to no central heating, which is why coal smoke and a valley setting combine to give it severe winter air pollution. Its climate is brutal enough that it is regularly described as the coldest national capital on Earth.

The Mongol empire's capital was Karakorum, far to the west, whose site is marked today by a monastery built from its stones.