The Río de las Juntas is a significant waterway in the La Rioja province of Argentina, offering a unique angling destination within the region's arid landscapes. As a freestone river, its flow is primarily dependent on seasonal precipitation and snowmelt from the surrounding mountains, creating a dynamic environment that supports a distinct fishery. The river's course features a mix of riffles, runs, and deeper pools, with a substrate ranging from cobble and gravel to larger boulders, particularly in its upper and middle reaches. The riparian zone is characterized by native vegetation that provides crucial shade and cover along the banks.