President Costa e Silva Bridge, commonly known as the Rio-Niteroi Bridge, is a box girder bridge located at Guanabara Bay, in the State of Rio de Janeiro in Brazil. It connects the cities of Rio de Janeiro and the municipality of Niteroi. It is currently the longest prestressed concrete bridge in the southern hemisphere, and the sixth longest in the world. From its completion in 1974 until 1985 it was the worlds second-longest bridge. 8.25 miles.