The Podkamennaya Tunguska (Russian: Подкаменная Тунгуска, literally Tunguska under the stones, also Middle Tunguska or Stony Tunguska) is a river in Krasnoyarsk Krai, Russia. It is an eastern tributary of the Yenisei and has a length of 1,160 miles (1,870 km). The name of the river comes from the fact that it flows under pebble fields without open water. As early as 1610 Russians from Mangazeya had passed the Stony Tunguska's confluence with the Yenisei; by the 1620s Mangazeya Cossacks and trappers had ascended it seeking fur-tribute from the local Tungus clans.