Most bridges carrying roads over canals have towpaths under them. Where they don’t, the horse usually had to cross the road. But just occasionally, you’ll spot one with a separate tunnel intended for horses – you can tell by its shape that it isn’t just for pedestrians. This one’s at Marple Locks – but there’s a very unusual one on the northern Grand Union at Shrewley, where the canal passes through a tunnel (without towpath), but at the northern portal, the horse path begins its journey over the top of the hill by climbing through a separate steeply-graded tunnel of its own. And at Cosgrove, there’s a similarly horse-shaped tunnel under the canal, providing a handy link today from the towpath to the village.