Well its not exactly an abandoned track as it was a temporary circuit but looking back it had some note as to the way karting was brought to the mass market..............
I raced at he very first "corporate" racing event on a temporary track in Camberwell, not the bus garage that came later, but in the walled area of the local park.
One side of the track has chain link fencing and people wandering in the park stopped to stare, they had not seen anything like it!
I seem to recall it was organised by Bob Pope who had acquired/ borrowed the kart's following school use which he was involved in.
I got my employer to sponsor the team I was in and we won the event.
The first event lead to another shortly after and "corporate" karting as we know it had been born.