Mocona Falls, also known as Yucumã Falls, is located in the Uruguay river, in the province of Misiones, in Argentina, 337 kilometers from the city of Posadas and 322 kilometers from Iguazu Falls. Since the Uruguay river acts as a natural border between Argentina and Brazil, this unique geological feature is shared by both countries. The name Moconá means “to swallow everything” in the Guarani language and is used mostly in Argentina. Yucumã means “the big fall” and is popular in Brazil.
An unusual feature of the Uruguay River is the presence of a submerged canyon or trench at the bottom of the river channel. The canyon, which is believed to have formed during the Ice Age, when the climate was drier and the river was narrower, is up to 100 meters deep and 15 - 30% of the width of the river. The canyon is only visible in two places, one of which is the Moconá Falls.
The falls itself are not visible for 150 days a year when the river is full. During this period, the falls become more like rapids. When water level becomes low and falls below the edge of the canyon, it starts spilling into the now exposed canyon, and the Mocona Falls is formed. Depending on the volume of the water dragged by the Uruguay River, the height of the falls varies from five to seven meters. The width of the waterfall is also subjected to water volume ranging between 1,800 meters and 3,000 meters wide.
The area where the Moconá falls are located is considered a Provincial Park which include the Yabotí Biosphere Reserve. Countless lodges have been settled down in the area which provide accommodation for visitors in search of water activities such as rubber boat rafting, canoe outings, kayaking and safaris along the river and creeks around this wetland.
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