If you're not sizzling in the sun on the beach or doing your laps in an Omani swimming pool, you should cover up your swimwear as soon as possible. Wearing them in public areas is prohibited in Oman. T-shirt and shorts are quickly slipped over and promptly relieve you of such problems. Also, a swimsuit is preferred over a bikini. "Topless" or even nudism are completely frowned upon. As for shoes, on the other hand, flip-flops and sandals are allowed even outside the hotel facilities.