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For centuries, and certainly into the early nineteenth century, goods were transported by packhorses, occasionally in ‘gangs’ of 18 or more but perhaps more usually in small groups. They followed customary tracks and roads, up hill and down dale, crossing numerous rivers and streams en route, and yet there is no entry in the OED for the term ‘pack-horse bridge’. It has been used frequently enough by transport historians in recent years, as when W.B. Crump wrote about ‘causeys’ and claimed that they ‘originated, along with the pack-horse bridges, in the sixteenth century’. Now, any bridge that is old and narrow and has a single arch is likely to find itself described as a packhorse bridge. There were alternative words: bridlesty bridge was recorded in 1688 and ‘horse bridge’ was quite frequent from the late sixteenth century. In 1598, the West Riding magistrates ordered the inhabitants of Trumfleet and Thorpe to make the horse bridge sufficient between trumfleete Marshe and thorpe Marshe … upon payne of xls. The context suggests that this may have been a causeway, but the term occurs in all three Ridings after that date and some of the bridges so described seem likely to have been what we now call packhorse bridges. ‘Evill-slack bridge’ in Skelton near York was also a ‘horse bridge’ in 1606. A later word was ‘pack and prime bridge’, recorded in 1798 but probably much older, since the term ’pack and prime way’ is on record from 1628.