Masirah is a long, flat, windswept island about 15 km off Oman's south-east coast, a two-hour ferry ride from the mainland at Shannah. It is nearly 65 km from end to end but never more than a few kilometres wide, with a population of around 12,000 people — mostly fishermen — scattered in small villages along the coast. There is almost nothing built up here. The interior is arid and empty; the western shore faces the mainland across a shallow turquoise channel; the eastern, windward shore has an uninterrupted 30-kilometre stretch of empty white-sand beach facing the open Arabian Sea.
The island's main claim to fame is ecological: between May and September, green turtles and, in smaller numbers, loggerheads, olive ridleys and hawksbills come ashore at night on the eastern beaches in what is one of the largest sea-turtle nesting aggregations in the Indian Ocean. The best beaches are in the north-east around Ras Hilf, and locals or the island's few small hotels can arrange nighttime turtle walks in season. The strong offshore winds and consistent surf also make Masirah one of the best kitesurfing and windsurfing destinations in the Gulf, particularly from June to September when the monsoon winds blow steadily across the island.
There is very little to do beyond that. There are no towns of any size, no restaurants except at the hotels, no nightlife, and no tourist infrastructure. That is, of course, the point. Bring what you need, rent a 4x4 from the ferry port, and plan to camp on the beach or stay at one of the handful of modest guesthouses in Hilf.