On the 1971 OS Quarter Inch map, the route is still the B5400
Whilst on the 1972 revision, the A5129 is shown
The now-unclassified former A5129 Kegworth High Street
The A5129 was a short A-road in north Leicestershire. Originally unclassified, it became the B5400 in the late 1920s. Following the lengthening of the runway of East Midlands Airport in the 1960s the road was upgraded in 1971-2 and rerouted (the old road crossed the present runway) and became the A5129. The road later became the mainline of the A453, whilst the eastern end was declassified.
The road started on the A6 in Kegworth. It headed west along the High Street before leaving town along Ashby Road, soon crossing the M1 to the south of J24. The road then zigzagged around the airport perimeter to rejoin the original line of the B5400 and head west to meet the A453 to the east of Isley Walton, where the road ended.