Geograph - photograph every grid square

I note several references to the aqueduct bridge that crosses the Wharfe in this square. I'm not sure of its actual date of construction, but would guess the last decade of the 19th century. It was built by Bradford Corporation to carry the water pipe from Scar House reservoir at the head of Nidderdale to Chelker reservoir above Addingham, and thence on to the city of Bradford. The bridge used to be closed to walkers. The pipe over the bridge was exposed and large metal grids barred access at either end. I would guess that these were removed and the bridge adapted for walkers in the mid 1990's. I think I am also right in saying that water ran from Scar House to Chelker by gravity alone. A section of the water pipe is exposed on the lower slopes of Simon's Seat and in various gills along the western side of Nidderdale between How Stean and Greenhow Hill.