Fiordland is full of fiords, but only two are relatively accessible from the Southern Scenic Route. One is Doubtful Sound, which requires a boat trip across Lake Manapouri and then a bus over Wilmot Pass to the Sound.
To fully experience Doubtful Sound, arrange your trip with one of the operators based in Te Anau or Manapouri. They offer various options, including an overnight stay on a boat, recommended if your budget allows.
The photos shared by @rogerstravelpics are from an overnight stay.
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