The Sepik River (was named Kaiserin Augusta River, after the German Empress Augusta by the German colonial explorer Otto Finsch) /ˈseɪpɪk/ is the longest river on the island of New Guinea, and after the Fly and the Mamberamo the third largest by volume. The majority of the river flows through the Papua New Guinea (PNG) provinces of Sandaun and East Sepik, with a small section flowing through the Indonesian province of Papua.