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, the mosque has suffered considerable damage over the years, not least the destruction of a minaret during an earthquake in the 1970s. But the painstaking restoration goes on with the twin aims of uncovering and restoring early inscriptions while leaving no trace of the recent work. It’s quite a challenge. If you get chatting with the architects in charge they might (no guarantees here) let you take a look at the remains of a fine mihrab believed to date from the early Islamic period, locked away in the southwest corner. Also worth finding are the reliefs in the rooms high above the main iwan.