A correction to the reviews below: be at Wadi Shab well before 4pm.
First, you will have to walk for about 45min each way.
Second you must take a boat to the other side if your camera ain't waterproof.
Third, the ferry people are reluctant to get you to the inner side if you arrive past 4. The ferry service across the river closes at 5pm (at least in mid October).
Ferry service costs 0.200 RO per person and way (40 Euro Cents at the time of writing).
Ps: if you arrive too late for Wadi Shab drive for 2km to Wadi Tiwi (fully accessible by car).
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