The Forth Bridge is a cantilever railway bridge across the Firth of Forth in the east of Scotland, west of central Edinburgh. Completed in 1890, it is considered a symbol of Scotland (having been voted Scotland's greatest man-made wonder in 2016), and is a UNESCO World Heritage Site. It was designed by English engineers Sir John Fowler and Sir Benjamin Baker. It is sometimes referred to as the Forth Rail Bridge (to distinguish it from the adjacent Forth Road Bridge), although this has never been its official name. Construction of the bridge began in 1882 and it was opened on 4 March 1890 by the Duke of Rothesay, the future Edward VII. The bridge carries the Edinburgh–Aberdeen line across the Forth between the villages of South Queensferry and North Queensferry and has a total length of . When it opened it had the longest single cantilever bridge span in the world, until 1919 when the Quebec Bridge in Canada was completed. It continues to be the world's second-longest single cantilever span, with a span of . The bridge and its associated railway infrastructure are owned by Network Rail. History of the Forth Crossing Before the construction of the bridge, ferries were used to cross the Firth. In 1806, a pair of tunnels, one for each direction, was proposed, and in 1818 James Anderson produced a design for a three-span suspension bridge close to the site of the present one. Calling for approximately of iron, Wilhelm Westhofen said of it "and this quantity [of iron] distributed over the length would have given it a very light and slender appearance, so light indeed that on a dull day it would hardly have been visible, and after a heavy gale probably no longer to be seen on a clear day either". For the railway age, Thomas Bouch designed for the Edinburgh and Northern Railway a roll-on/roll-off ferry between Granton and Burntisland that opened in 1850, which proved so successful that another was ordered for the Tay.