Although the National League South has a lot of clubs around London, just as the north does, to a lesser degree, around Manchester, it also has the longest journeys. I know they share at Torquay now, but Truro to Chelmsford, for example, is a lot further than Blyth to Brackley. I certainly haven't tried to work it out, but we must have some of the least travelling in National North, as we are very central for the division, and have lots of local derbies. You can argue that there should perhaps be three divisions at this level, as there used to be, but many clubs have much more travelling than us at present.
Incidentally, Gloucester City no longer play at Cheltenham nowadays, but at Evesham, which is north of Brackley, so they must be potential candidates for a switch, whatever happens.