Orenburg Oblast is a federal subject of Russia. Its administrative center is the city of Orenburg. From 1938 to 1957, it bore the name Chkalov Oblast in honor of Valery Chkalov. Population: 1,862,767.
Wikipedia https://en.wikipedia.org/wiki/Orenburg_Oblast
Coordinates 51°46'1.649" N 55°5'52.266" E