The Karun River Bridge is one of two large steel truss arches that were necessary to carry a former road across the deep reservoir created by the massive Karun 3 dam. Upon its completion in 2005, the West span became the highest bridge in the Middle East, surpassing the record previously held by Iran’s 35 year old Ghotour bridge. The Karun 3 Dam is one of a series of huge hydroelectric projects that have been built along the Karun River which has the greatest discharge of any river in Iran and is hence the most important power producing waterway in the country. At 205 meters from top to bottom, the double curvature Karun 3 Dam became the tallest in the country upon its completion in 2005. The even larger Karun 4 Dam began operation in 2011 with a foundation to crest height of 230 meters. For a size comparison, the famous Hoover Dam near Las Vegas is slightly higher then Karun 3 but slightly lower then Karun 4.
The larger West crossing over the main channel of the Karun River has a hinge to hinge span of 252 meters with an overall length of 336 meters. The smaller East span crosses a smaller side canyon with a span of approximately 175 meters and a height of approximately 130 meters. The West span has a much greater span to rise ratio then the East bridge since both are of equal height above the reservoir. The Karun River is sometimes spelled as Karoon or Karoun.