Sir Benjamin Baker KCB KCMG FRS FRSE (31 March 1840 – 19 May 1907) was an English civil engineer who worked in mid to late Victorian era.

He made many other notable contributions to civil engineering, including his work as an expert witness at the public inquiry into the Tay Bridge disaster.

He was born in Keyford, which is now part of Frome, Somerset in 1840, the son of Benjamin Baker, principal assistant at Tondu Ironworks, and Sarah Hollis.

[2] He was educated at Cheltenham Grammar School and, at the age of 16, became an apprentice at Messrs Price and Fox at the Neath Abbey Iron Works.

He designed the cylindrical vessel in which Cleopatra's Needle, now standing on the Thames Embankment, London, was brought over from Egypt to England in 1877–1878.

He published a timely book on Long Railway Bridges in the 1870s which advocated the introduction of steel, and showed that much longer spans were possible using this material.

Baker said in his statement to the court that he had built over 12 miles (19 km) of railway viaduct, referring to his design of the elevated railroad in New York City in 1868, some of which still survives in Manhattan (unused).

Shortly afterwards he was engaged on the work which made his reputation with the general public: the design and erection of the Forth Bridge (1890) in collaboration with Sir John Fowler and William Arrol.

Baker promoted his design in numerous public lectures, and arranged demonstrations of the stability of the cantilever by using his assistants as stage props.

The bridge was opened on 4 March 1890 by the Prince of Wales, later King Edward VII, who drove home the last rivet, which was gold plated and suitably inscribed.

A contemporary repainting of the bridge commenced with a contract award in 2002, for a schedule of work expected to continue until March 2009, involving the application of 20,000 m2 of paint at an estimated cost of £13M a year.

In a report produced by JE Jacobs, Grant Thornton and Faber Maunsell in 2007 which reviewed the alternative options for a second road crossing, it was stated that the estimated working life of the Forth Bridge was in excess of 100 years.

[5] Ten years later at the formal opening of the first Aswan Dam, for which he was consulting engineer, he was appointed Knight Commander of the Order of the Bath (KCB).

Baker also played a large part in the introduction of the system widely adopted in London of constructing underground railways in deep tubular tunnels built up of cast iron segments.

He died at his home, Bowden Green, in Pangbourne, Berkshire where he lived in his later years and was buried in the village of Idbury in Oxfordshire, next to his mother.