Highlights include a map showing a thwarted extension of the Northern Line to Elstree, a pre-Beck chart showing the exact tunnel routes beneath London's streets, and the much maligned Hutchinson ...

The shafts from the Elstree Tunnel, ... View London LOOP in a larger map. ... The final stretch of the walk takes us through the woodland of Monken Hadley Common and on to Cockfosters Tube Station.