The Muscat Gate marks the main entrance to the old walled city and houses a small museum inside its two towers. The gate was the principal portal through which travellers and traders entered Old Muscat for centuries; the current structure dates from the mid-20th century but stands on the site of an older gate. Inside, the museum covers the history of Oman's ancient trade connections — frankincense, dates, horses, and fish — through maps, artefacts, and photographs from the early 20th century when Muscat was still a walled city with gates that closed at night.
The museum is compact and can be covered in under an hour. It's worth combining with a walk through Old Muscat itself: from the gate you can walk along the seafront past Al Alam Palace and the flanking forts in twenty minutes. Entry is free or requires a small fee. Hours can be irregular, so check before making a specific trip; mornings are the most reliable time to find it open.