t Woodford the two lanes of the M11 split apart and connect in a long sweep to the North Circular in a strange and convoluted junction. The shape of the junction makes little sense till you discover the gap in the middle was for a connection to the (never built) M12 motorway which was to go to the (never built) Maplin Airport.
The space left is now a nature reserve, this is the view from underneath the southbound carridgeway.