Lake Peipus

Lake Peipus spreads between the lands of Pskov and Livonia, receiving the Velikaya and Emajõgi and draining north through the Narva to the Gulf of Finland. Its broad waters connect a northern basin with Lake Pskov in the south through a narrower strait. In winter the lake freezes, turning a waterway into a surface over which armies could move. In 1242 Alexander Nevsky's Novgorodian forces defeated the Teutonic knights on the frozen southern lake in the battle remembered as the Battle on the Ice.