The Optina Pustyn is an Eastern Orthodox monastery for men. It is located on the Zhizdra River, 4 km from Kozelsk in Russia. According to the legend, it was founded at the end of the 14th century by a repentant robber named Opta (Optija), in monasticism - Macarius. The synodic of the Optina Convent of 1670, rewritten from an ancient synodic, testifies that as early as the 15th century, the Optina convent existed. In the 19th century, the Optina was the most important spiritual centre of the Russian Orthodox Church and served as the model for several other monasteries, including the nearby Shamordino Convent. It was particularly renowned as the centre of Russian Orthodox eldership. The Optina Pustyn was shut down by the Soviets in 1918, but the monastery was still held under the guise of an “agricultural artel” until 1923. On November 17, 1987, the Soviet government returned the Optina Pustyn monastery to the Russian Orthodox Church. https://en.wikipedia.org/wiki/Optina_Monastery
Kaluga Oblast is a federal subject of Russia (an oblast). Its administrative center is the city of Kaluga. It was created in 1944 out of four other oblasts: Moskva Oblast, Orel Oblast, Smolensk Oblast, and Tula Oblast. It is located at the historical region of the former Kaluga Governorate.