Like most ancient countries, Iran has experienced many invasions and internal conflicts over the centuries, and many of the necessary fortifications can still be seen. Tragically, one of the best-known and most complete of these, the fortified mud-brick city of Bam, was destroyed in an earthquake in 2003, with the loss of up to 15,000 lives.

    A much smaller mud-brick citadel can still be seen in Rayan, and restoration is underway to protect the crumbling walls and turn part of it into unique accommodation.

    The word "caravanserai" sounds so exotic that it can be easy to forget that these resting places are simply the desert equivalent of English hostelries or American staging posts. However there is no denying that their location and construction place caravanserai high on the list of things every tourist hopes to see. Many have been preserved or even rebuilt to modern standards, but most are in varying stages of decay from the inevitable erosion of their mud brick walls, or removal of building materials for use elsewhere.