Groot River (Gamtoos) (Large River) is situated in the Eastern Cape province of South Africa and originates at a point where two other rivers meet, the Kariega River and the Sout River, although they enter the Beervle Dam as the Sout River. Beyond the dam, the river becomes the Groot River, running southeast, first the small Krom River joins its forces, then the Kraai River and the Koegero River and yet further the Plessis River; still further downstream the Heuningklip River comes to strengthen it even further, near Steytletville it turn a little south before going east again, there the Grootvlei River, Gass River and Soutkloof River add to the swelling waters; it then suddenly turns south again, before the Kouga River joins it (the Kouga has then just left the Kouga Dam behind it); from there it gets a new name, the Gamtoos River.