I will be in Queenstown for a week (w/a rental car) and plan to drive to Milford Sound. What else is a must see around there ? And any other unique activities that might not make the top 'Trip Advisor' lists. Budget flexible. Thanks!
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What time of year will this be?
It's not recommended to self drive in winter, it's a long journey and many people prefer to use a coach tour. There's also the option of driving to Te Anau for an overnight stay, visit the glow worm caves and go to Milford from there, also you can do an over night cruise on Doubtful Sound
It's a fairly sparse area comparatively, check out the NZ Frenzy South Island guide for "off the beaten track" ideas.