Historedia
EuropeEvent

Erection of the Iron Bridge

When
1773–1781
Where
Ironbridge Gorge, River Severn; Ironbridge Gorge crossing of the River Severn
Episodes
5

The Iron Bridge, a cast iron arch spanning the River Severn's Ironbridge Gorge in Shropshire, first spanned the river on 2 July 1779 when its ribs were lifted into place. Proposed by the architect Pritchard and cast at Coalbrookdale, it opened to traffic on 1 January 1781 as the first major bridge in the world made of cast iron.

Episodes

  1. 1773 · Ironbridge Gorge, River SevernPritchard proposes a cast iron bridge

    In 1773, architect Thomas Farnolls Pritchard wrote to ironmaster John Wilkinson suggesting a bridge built of cast iron.

  2. 1777–1778 · Ironbridge Gorge crossing of the River SevernMasonry and abutments constructed

    The masonry and abutments of the Iron Bridge were constructed between 1777 and 1778, before the iron ribs were raised.

  3. July 1777 · Ironbridge Gorge crossing of the River SevernSpan revised in July 1777

    In July 1777 the bridge's span was decreased to 90 feet, then increased to 100 feet 6 inches, possibly for a towpath.

  4. 2 July 1779 · Ironbridge Gorge crossing of the River SevernRibs lifted and bridge first spans the river

    The cast iron ribs were lifted into place in summer 1779, and the bridge first spanned the River Severn on 2 July 1779.

  5. 1 January 1781 · Ironbridge Gorge crossing of the River SevernBridge opens to traffic

    The Iron Bridge was opened to traffic on 1 January 1781, becoming the first major bridge in the world made of cast iron.

Background and detail

Background. The deep Ironbridge Gorge, formed by glacial action at the end of the last ice age, exposed coal, iron ore, limestone, and fire clay near the surface, but its unstable banks and the need to keep the Severn navigable made bridging the river there difficult. The Severn was a key trading route yet a barrier between the industrial parishes of Broseley and Madeley, with the nearest bridge at Buildwas.

Proposal and Design. In 1773, architect Thomas Farnolls Pritchard wrote to his 'iron mad' friend, the Broseley ironmaster John Wilkinson, suggesting a bridge of cast iron. Pritchard proposed a single-span iron bridge to cope with the unstable banks and preserve a navigable channel. In July 1777 the span was reduced to 90 feet, then increased to 100 feet 6 inches, possibly to accommodate a towpath.

Erection in 1779. The masonry and abutments were built between 1777 and 1778, and the ribs were lifted into place in the summer of 1779. The bridge first spanned the river on 2 July 1779. The two outer ribs carry the inscription: "This bridge was cast at Coalbrook-Dale and erected in the year MDCCLXXIX". A 1997-discovered watercolour by Elias Martin shows the bridge under construction that year.

Significance. Opened in 1781, it was the first major bridge in the world made of cast iron and the first bridge of significant size built of metal, exerting considerable influence on technology and architecture. Its success inspired widespread use of cast iron as a structural material, and it is celebrated as a symbol of the Industrial Revolution.

People involved

Sources

  1. The Iron Bridge Wikipedia, revision of 2026-09-06

Machine-drafted from the cited Wikipedia passages and checked by a reviewing model, not by a human editor. Every passage cites the revision it was written from; dates and places follow those passages.