Tuul River in the context of "Khamag Mongol"

Ulaanbaatar is the capital and most populous city of Mongolia. It has a population of 1.67 million, and it is the coldest capital city in the world by average yearly temperature. The municipality is located in north central Mongolia at an elevation of about 1,300 metres (4,300 ft) in a valley on the Tuul River. The city was founded in 1639 as a nomadic Buddhist monastic centre, changing location 29 times, and was permanently settled at its modern location in 1778.

During its early years, as Örgöö (anglicized as Urga), it became Mongolia's preeminent religious centre and seat of the Jebtsundamba Khutuktu, the spiritual head of the Gelug lineage of Tibetan Buddhism in Mongolia. Following the regulation of Qing-Russian trade by the Treaty of Kyakhta in 1727, a caravan route between Beijing and Kyakhta opened up, along which the city was eventually settled. With the collapse of the Qing dynasty in 1911, the city was a focal point for independence efforts, leading to the proclamation of the Bogd Khanate in 1911 led by the 8th Jebtsundamba Khutuktu, or Bogd Khan, and again during the communist revolution of 1921. With the proclamation of the Mongolian People's Republic in 1924, the city was officially renamed Ulaanbaatar and declared the country's capital.

Bogd Khan Mountain (Mongolian: Богд хан-уул; lit. 'Mount St. Khan') is a mountain in Mongolia that overlooks the nation's capital, Ulaanbaatar, from a height of 2,261 metres (7,418 ft) to the south of the city.

The mountain lies within the Bogd Khan Uul Biosphere Reserve.

The Keraites (also Kerait, Kereit, Khereid, Kazakh: керейт; Kyrgyz: керей; Mongolian: ᠬᠡᠷᠢᠶᠡᠳ, Хэрэйд; Nogai: Кереит; Uzbek: Kerait; Chinese: 克烈, Persian: کرایت) were one of the five dominant Turco-Mongol tribal confederations (khanates) in the Altai-Sayan region during the 12th century. They had converted to the Church of the East (Nestorianism) in the early 11th century and are one of the possible sources of the European Prester John legend.

Their original territory was expansive, corresponding to much of what is now Mongolia. Vasily Bartold (1913) located them along the upper Onon and Kherlen rivers and along the Tuul river. They were defeated by Genghis Khan in 1203 and became influential in the rise of the Mongol Empire, and were gradually absorbed into the succeeding Mongol khanates during the 13th century.

Tümengken Choghtu Khong Tayiji (Classical Mongolian: ᠲᠦᠮᠡᠩᠬᠡᠨ
ᠴᠣᠭᠲᠤ
ᠬᠤᠩ
ᠲᠠᠶᠢᠵᠢ, Tümengken čoγtu qong tayiǰi; modern Mongolian: Түмэнхэн Цогт Хунтайж, [ˈtumən.xɛŋ ˈt͡sɔx.tə ˈxuŋ.tæt͡ʃ], Tümenkhen Tsogt Khun Taij; Chinese: 綽克圖台吉; 1581–1637), was a noble in Northern Khalkha. He expanded into Amdo (present-day Qinghai) to help the Karma Kagyu sect of Tibetan Buddhism but was overthrown by Güshi Khan, who supported the rival Gelug sect. He is also known for writing a famous poem in 1621, which was transcribed on the surface of a rock in 1624, and still exists.

He established a base on the Tuul river. Known as an intellectual, he embraced the Karma sect and built monasteries and castles. In 1601, he built the White Castle, or the White House of Choghtu Khong Tayiji.