The Forth Rail Bridge is a railway bridge over the Firth of Forth in the east of Scotland, to the east of the Forth Road Bridge, and west of Edinburgh.

The earlier bridge project got as far as the laying of the foundation stone, but was doomed to failure due to the collapse of the Tay Rail Bridge, designed by Sir Thomas Bouch who had also submitted the Forth Rail Bridge design.

The present day bridge is, even today, regarded as an engineering marvel. It consists of three massive cantilever towers, each 104 m tall. The designers were Sir John Fowler and Sir Benjamin Baker, and the bridge was constructed by Sir William Arrol between 1883 and 1890. 57 lives were lost during construction, and more than 55,000 tons of steel were used, as well as 18,122 cubic metres of granite and eight million rivets. The bridge was opened by the Prince of Wales, later King Edward VII, who drove home that last rivet which was gold plated and suitably inscribed.

Although modern lightweight trains put fewer stresses on the bridge than the earlier heavy steam trains, the bridge needs constant maintenance. "Painting the Forth bridge" is a colloquial term for a never-ending task.