The biggest river in Dornod Province is the Khalkh River. This was the site of a major military confrontation in 1939 between the Empire of Japan and the combined forces of the Soviet Union. The battle was to have a significant influence of the subsequent course WW II. In 2019, Russia and Mongolia agreed to jointly celebrate the 80^th anniversary of the Victory of the Khalkh River. The decision was made by the presidents of both nations during the Vladivostok Economic Forum in September. In marking the anniversary, the two former allies will organise many events such as exhibitions, documentary films and movies.

In September, the 13th international expedition visited the site of the battle in search of the remains of soldiers from the Red Army. The team found the remains of ten soldiers: nine are Russian and one is Japanese.