or Orkhon River
River, northern Mongolia.
It is 698 mi (1,123 km) long and rises from the slopes of the Hangayn Mountains. It flows east, then north past Karakorum . The 8th-century funerary stelae discovered in the river's valley in 1889 contain some of the oldest known Turkic writing, called the Orhon inscriptions. The river is navigable for shallow-draft vessels only in July and August.