Bermejo River

The southern branch is the bed of the old Bermejo River, now an intermittent stream called Río Bermejito.

[2] The two branches rejoin at 25°39′S 60°11′W / 25.650°S 60.183°W / -25.650; -60.183,[3] near Villa Río Bermejito, forming the Lower Bermejo River.

[4] The river is born in a mountain range known as Sierra de Santa Victoria around coordinates 22°00′14″S 64°57′30″W / 22.00389°S 64.95833°W / -22.00389; -64.95833 near Tarija, a few kilometres southeast of Chaguaya in Bolivia, and not far from La Quiaca, Jujuy Province, Argentina.

On the shores of this river can still be seen the ruins of the former towns of Concepcion del Bermejo, San Bernardo de Vértiz (25°8′S 61°8′W / 25.133°S 61.133°W / -25.133; -61.133[5]), and La Cangayé (25°36′S 60°19′W / 25.600°S 60.317°W / -25.600; -60.317[6]).

The river carries red-coloured sediments and produces irregular accumulations that can even alter its course, leaving the older paths as wet depressions.

Map of the Rio de la Plata Basin , showing the Bermejo River joining the Paraguay River north of Resistencia .
The Bermejo River at Presidencia Roca in the Argentine Gran Chaco
The Bermejo seen from Puente Lavalle upstream.