sentences:  The South Mimms junction was originally intended to be the end of a short spur connecting the A1 to the M16.The main alignment of the M16 would have continued south-west of the junction towards Radlett and Bushey.Evidence of this unbuilt alignment remains in the wide gap between the carriageways to the east of the South Mimms junction which would have been the point at which the spur would have separated from the continuing carriageway.