The Iron Trunk

Today's walk. Cosgrove Aquaduct, completed 1811. It takes the Grand Union Canal, in the foreground, over the valley of the River Great Ouse, which you can see below. Designed by Benjamin Bevan using Thomas Telford's cast iron trough method: the white line is the top of that thin edge of the trough.  It replaced an earlier structure which itself replaced a system of nine locks down and up again. This is the lowest point on the GUC between the summits at Tring and Braunston.

Extra: another view.