The expansive Imam Mosque is worth a look specifically if you’re interested in the process of rehabilitating old buildings. Dating from the early Islamic period, restoration work has uncovered the remains of a fine mihrab (niche inside a mosque indicating the direction of Mecca) believed to date from the early Islamic period (in the southwest corner), and on the roof a series of three unusual mihrab-style niches, the origins of which remain a mystery. To see them, ask the attendant nicely or come with a guide.