Why it's the capital
Muscat's port was already known in Roman times: the Greek geographer Ptolemy called it Cryptus Portus, the Hidden Port. In 1793 Oman's capital was moved here from Rustaq.
Capital of OmanMuscat stretches along the Gulf of Oman in the northeast of Oman, with the Hajar Mountains behind it, not far from the Strait of Hormuz.
Muscat's port was already known in Roman times: the Greek geographer Ptolemy called it Cryptus Portus, the Hidden Port. In 1793 Oman's capital was moved here from Rustaq.
Follow Oman's coast south-east from the Strait of Hormuz towards the eastern tip of Arabia. Muscat is on that coast, facing the Gulf of Oman, before you reach the tip.
Sources: Wikipedia: Muscat