The Gandan Monastery (Gandantegchinlen Khiid) is the largest monastery in Mongolia and was built in 1838 by the fourth Bogd Gegeen. It's name means "the great place of complete joy," but it was ravaged during the religious purges of 1937. The monastery was used as a "show monastery" for foreign visitors until 1990 to cover up the destruction of Mongolia's religious heritage. Now, over 500 monks worship here.
The Ochidara Temple is used for most significant ceremonies but if you continue further along the path you will come to the Migjid Janraisig Süm, the main attraction. The white walls of this temple are lined with images of Ayush, the Buddha of longevity, which face the impressive statue of Migjid Janraisig. The statue, meaning 'The Lord Who Looks in Every Direction', sits 26.5m-high, weighs 20 tons, and is made from copper and gilded with gold donated from Nepal and Japan. It is covered with gold brocade, over 500m of silk, and precious jewels. It contains 27 tons of medicinal herbs, 334 sutras, two million bundles of mantras, and an entire ger with furniture at its base!