Inner Mongolia (Traditional Chinese: 內蒙古; Simplified Chinese: 内蒙古; Hanyu Pinyin: Nèi Ménggǔ) officially the Inner Mongolia Autonomous Region (Traditional: 內蒙古自治區; Simplified: 内蒙古自治区; Pinyin: Nèi Ménggǔ zìzhìqū) also Southern Mongolia, is an autonomous region of China, extending for more than a thousand miles along China's northern frontier with Mongolia. Most of its area is desert or semi-desert, since most of it lies in the cold, arid Gobi Desert. The capital city is Hohhot, the largest city is Baotou.