Geography:

Misiones covers a territory of 30.719 km (or 29.704 km according to the Geographic Military Institute) and 90% of our borders are water. It shares borders with Paraguay (River Parana) and Brazil (Rivers Uruguay and Iguazú) and covers 1% of Argentina’s continental surface and holds 2.4% of the country’s population (789.677 inhabitants according to national survey of population 1991). Today the figure is closer to 900.000 inhabitants, 63% living in urban areas and 37% in rural.“Misiones” is an area associated with the ancient Guarani and Jesuit ruins, a space between the subtropical forest and country and pasture which the three countries share between the parallels of 25º 30´ to 28º latitude and along the meridian of 52 º 30 to 57 º longitudes.  

 

Misiones forms part of Brazil’s high plateau, the dominant feature being its volcanic rock, Mesozoic basalt (“Serra Geral” formation) and lime conglomeration. These rocks have been formed throughout time with the aid of water and vegetation. In certain areas the rocks surround the central parts of the large rivers, dorsal or high plateau which goes from south to northeast along the national route 14. The landscape is hilly and the orientation of numerous hills produces thousands of rivers - torrents of water, which cut through the top of the earth to disgorge in the rivers of Parana, Uruguay and Iguazú.  

The rivers are constituted of tectonic lineaments and produce deep-water canyons such as the river Parana, which at the junction with the river Iguazú

 

Is 300m wide and which grows to a width of 2,500m in Posadas.  

There are also corridors or mud banks, which are natural sandbanks of basalt through which the waters pass to reach the deeper canals of the river. 

 

Climate:  

In Bernardo de Irigoyen (853 m. above sea level) by the stream Pepirí Guazú (northeast) there is an estimated annual rainfall of more than 2,000 mm., as a result of the exposure to the advancement of the humid tropical air. The rainfalls diminish steadily towards the southwest and Posadas, where an average of 1,600 mm. of rain has been registered.  

The annual average temperature is almost always higher than 20ºC - in January 26ºC and in July 15ºC.  In mountainous areas the earth produces a cold microclimate on the slopes of the hill ranges in the north/northeast. Along the lower areas of the great rivers thermal regulation practically controls the risk of freezing. At the higher levels of 300 m. above sea levels there is a possibility of snow. At the locations of San Pedro (530 m. above sea level) and Bernardo de Irigoyen winters are far cooler with an average temperature of 12ºC during July.