"Mizter T" wrote

Going south, for any destination from Stockwell southwards passengers
should stay on the Victoria line, so that leaves Kennington and Oval
as the only other two destinations where one must make a more awkward
change.

though from north of Kings Cross on the Victoria Line one can reach these
stations by one cross-platform change at Euston (not entirely intuitive, as
it involves doubling back via Kings Cross).

Peter