Optina Pustyn, Eastern Orthodox monastery in Kozelsk, Russia

Optina Pustyn is a walled monastery with an almost square plan, its low fence and four corner towers built between 1832 and 1839. At the center stands the Cathedral of the Presentation of the Blessed Virgin Mary, surrounded in a cross pattern by the Church of Mary of Egypt to the north, the Kazan Church of 1811 to the south, and the Church of the Vladimir Icon to the east. A tall pale-green bell tower with a blue dome rises beside the pink gate church and the large blue dome with gold stars.

Tradition attributes the monastery's founding to Opta, a repentant robber who took the name Makary, though the date is uncertain and the 1670 Synodicon records a community already in the 15th century. The first written evidence comes from Kozelsk scribe books of 1629–1631 under Boris Godunov. In 1724 it was abolished and attached to the Belëv monastery, then restored in 1726 by order of Catherine I.

The monastery was the centre of Russian Orthodox eldership, and its startsy drew pilgrims from across the country. The name probably comes from the Russian word for "living together", as nuns were allowed in the cloister before 1504. The startsy are commemorated together on October 10.

Regular bus services run multiple times daily between the monastery and Moscow, with the complete journey taking around five hours. Visitors should wear appropriate clothing as this is an active religious site.

The writer Konstantin Leontyev lived at the monastery for four years and took monastic vows there. The Kireyevsky brothers, Slavophile thinkers, helped build its library and are buried within the monastery walls.