In 12 km from the Moscow regional town Serpukhov there is one of the few places in Russia where bisons live. By the beginning of the XX century they were exterminated, only several animals survived in the zoological gardens. This species in Russia is rehabilitated in the Northern Caucasus and there, in the Oka reserve. Beside the bison, one can also see a spotty deer, a Russian musk-rat and rare birds there. The natural zones of the reserve go down in terraces to the Oka, the biggest tributary of the Volga.
