Just when the masonry arch bridge was reaching its peak around the beginning of the 20th Century, reinforced concrete arrived on the scene. Since then, it has become the major construction material for bridges as it has for most structural and civil engineering applications, with its intrinsic versatility, design flexibility and, above all, natural durability.

Although several British engineers had been using concrete early in the 19th Century, its use in British bridges did not develop until the latter half of the 20th Century. It is estimated that at least 75% of the Highways Agency concrete bridge stock has been built since 1960.

In contrast, concrete arches were being buit in continental Europe as far back as the 1850s by Gariel, Coignet and then Monier. The earliest known example of a mass concrete bridge in the UK, using lime concrete, was on the District Line, near Cromwell Road, West London, designed by Thomas Marr Johnson for Sir John Fowler and built c.1865. Other British engineers began to use plain concrete for bridge superstructures, notably Philip Brannan, who erected a three-span concrete arch, including a 50ft middle span, at Seaton in Devon in 1877.

Railway engineers were also active at this time, using plain concrete on the Dochart Viaduct, with the London and South Western Railway and the West Highland Railway using mass concrete towards the end of the century. Plain concrete was used on the Carrington Viaduct (1903) and the first reinforced concrete railway bridges were those designed by Mouchel (Bristol, 1907) and Coignet (Bargoed, Wales). The first British reinfotced concrete railway bridge was the 28ft. span structure built in Dundee, Scotland in 1903. By the 1930's there was a significant increase in the use of reinforced concrete.

The use of reinforced concrete probably started with the Homersfield Bridge over the River Waveney on the Norfolk/Suffolk border in 1870, when iron was embedded in concrete, but it was not until the first decade of the 20th Century that reinforcement, as we know it today, was introduced. This was due almost entirely to L.G. Mouchel, the UK agents for the Hennebique system. The first project in the UK was an 18ft span bridge at Chewton Glen in Hampshire in 1902, followed two years later by a 40ft span beam and slab bridge at Sutton Drain in Hull.

Homersfield Bridge dates from 1870. The arch is reinforced with a wrought iron framework encased in concrete. The balustrade is of cast iron ornately decorated.