Jebel Akhdar — the Green Mountain — is the high plateau of the western Hajar range, about an hour's drive north-east of Nizwa. The summit area sits at 2,000 metres, cool enough to grow apples, apricots and roses that no other corner of the Arabian peninsula will support.
The road up is a serious one — a 4WD is required by law past the police checkpoint at the base, and rental cars on the wrong side of that rule will be turned back. Once on top, the main attractions are the Saiq plateau villages, the terraced rose gardens at Al Ayn and Sayq, the dramatic Wadi Bani Habib hiking route, and the abandoned cliff-side village of As Sab. The Anantara and Alila hotels on the rim are world-class viewpoints if you can afford a drink at sunset.