What looks like a path was actually a railway back in the day. A railway, opened in 1858, used to run between Dunstable and Welwyn Junction (now the site of Welwyn Garden City station where the branch used to join the main Great Northern Line). Like a lot of branch railways in England, this particular branch line was closed by Dr. Beeching in 1965 following his report into the future of Britain's railways in 1963. Some 5,000 miles of railway was cut to make the railways more cost-effective. You can walk along the former railway line to near Wheathampstead to the west of Welwyn Garden City.
If you are used to travelling by train through Welwyn Garden City then the sight of the lovely,now disused, Shredded Wheat factory will be reassuringly familiar.