Bustling Ad Dirah owes its old-world vibe to landmarks like Al-Masmak Fortress, which traces Saudi history through photos and weaponry in an 1860s mud-and-clay building. The huge Imam Turki Bin Abdullah Grand Mosque, with its limestone facade, overlooks central Alsafat Square. Stalls piled high with spices, gold, and carpets fill long-standing Souq Al Zel, as do tiny shops selling coffee and traditional sweets.