Barford Interchange is junction 14 of the M40.
The M40 north of here took over the A41 Warwick bypass. This junction is the tie-in. A roundabout provides a u-turn opportunity for non-motorway traffic that happened to go down this road. This avoids a single-carriageway motorway spur. M40 J13 provides the south facing slips towards London.
Early 1970s plan for the junction
Early plans for the M40
favoured an online upgrade of the southern section of the recently completed Warwick Bypass. The roundabout at the eastern end of the bypass would have been enlarged with the M40 passing above. This junction would have provided all movements so there would have been no junction in the vicinity of J13.