The trip Oman's visitors agree on: Wadi Shab — a small boat crosses the entrance, an hour's walk between walls, palms and emerald pools, then the three-pool swim to the hidden cave where a waterfall roars inside rock: an unforgettable crowning. Reaching the fall demands real swimming through a narrow passage — for non-swimmers the first pools satisfy wholly; water shoes and a dry pouch for the phone, starting early against heat and noon crowds; two hours from Muscat, golden-paired with Bimmah in one coast day.