The Paraná Tunnel, or to use its official name: Túnel Subfluvial Raúl Uranga - Carlos Sylvestre Begnis, is a unique solution to the region’s major engineering and transport challenge.
Finished in 1962, it crosses beneath the Paraná River between the capital of Entre Ríos province, Paraná, and Santa Cándida Island, 15 km from Santa Fe.
The region’s two major rivers, the Paraná and Uruguay, cut the provinces of Entre Rios, Corrientes, and Misiones off from the rest of the country so completely that they could only be reached by ship or by air.
A series of raft ferries transported vehicles across the river, and for 20 years this 50 minute service was the only way for cars and trucks to cross the mighty Paraná.
This isolation impacted the development of these regions and limited their ability to trade and communicate with the rest of Argentina.
After years of failed attempts to plan and build a bridge, ideas for a tunnel were developed throughout the 1950s.
In 1960, the local governments of Santa Fe and Paraná committed to build the tunnel to finally provide road access between these two highly populated and economically important provinces.
The tunnel is made of immersed tubes, each measuring 65 metres long and weighing 4,500 tonnes.
Tunnel elements were built and assembled in a dry dock on the river bank and then floated into position before being sunk onto the river bed.
The tunnel runs for nearly three kilometres under the river, and at its deepest point is 32 metres below the average surface level of the river.
The tunnel remained the only way in the region to cross the Paraná River for 40 years, until a bridge was eventually built 120 km further south in 2003.