New Bridges

The New Bridges at Hemingford Grey, dating to 1822, form a remarkable single causeway and bridge structure built for the Bury-Stratton Turnpike Trust, with the causeway itself originally owned by the Duke of Manchester. The bridges were likely designed by Thomas Gwyn Elger of Bedford, with William Biggs acting as surveyor and John Turner probably serving as master builder; a carved plaque, now eroded, bears the inscription "John Turner 1822." The construction was funded by a loan from trustee John Margetts, who also supplied bricks from his brickworks. Work began on April 8th 1822, and the 55 arches were completed in just 23 weeks, using approximately 1,250,000 bricks.

The structure is built of yellow gault brick and features fifty-five segmental arches divided by brick buttresses of two stages, the lower stage incorporating cut-waters. A band runs at road level, and the parapet is mostly stone coping, with some 19th-century brick replacement and repairs. The causeway itself is roughly 700 feet long. When the railway crossed the causeway in 1847, some arches were strengthened with a level crossing, but subsequent repairs have largely preserved the original structure, and much of the stone coping remains.

The New Bridges are a unique example in the UK, representing the longest road causeway with the greatest number of continuous brick arches. Predating later railway viaducts, it provides a significant insight into "Turnpike archaeology" and was noted by engineer Thomas Telford in 1826. Compared with other similar causeways, New Bridges is exceptionally extensive and comparatively unaltered.