Battle of the Sit River
The Battle of the Sit River was fought in the northern part of the present-day Sonkovsky District of Tver Oblast of Russia, close to the selo of "Bozhonka", on March 4, 1238 between the Mongol Hordes of Batu Khan and the Rus' under Grand Prince Yuri II of Vladimir-Suzdal during the Mongol invasion of Rus.