Description Longest Single-Pylon cable-stayed bridge in the world. The Ada bridge or Sava bridge is a new cable-stayed bridge currently under construction over the Sava river in Belgrade, Serbia. The bridge will cross over the tip of Ada Ciganlija island, connecting municipalities of Cukarica and Novi Beograd. The bridge pylon is located on the tip of the island which has been reinforced with large amounts of concrete and has been slightly enlarged to give a stronger foundation for the pylon. When finished, the bridge will be the longest Single-Pylon cable-stayed bridge in the world. The construction began in 2008 and is scheduled to be completed by 2013.