South Australia contains 324 separate Protected Areas with a total land area of 21,630,995 hectares(21.97% of the state’s area). 18 of these are National parks, totalling 4,337,430 hectares (4.41% of the state’s area).
... are these stations, all of which were at the far end of the Metropolitan Line, and stretch the definition of "tube station" a little:
Waddesdon tube ...