The Sakarya Viaduct () is a long railway bridge carrying the Ankara-Istanbul high-speed railway across the Sakarya River and its adjacent plain approximately west of Polatlñ, Turkey. The bridge is the fourth longest bridge in Turkey after the ÃÂanakkale 1915 Bridge and Osman Gazi Bridge and the Mount Bolu Viaducts as well as the longest railway bridge in the country.
Construction of the viaduct was started in 2007 and completed in 13 months. The bridge entered revenue service on 13 March 2009, with the opening of the railway from Ankara to Eskià Âehir.