Qaleh Ardeshir is a sprawling fortified site on a rocky outcrop east of the city, traditionally attributed to the 3rd-century Sasanian king Ardeshir I (though most of the visible structures are later). The walls, watchtowers, and the cisterns inside the keep are weathered but legible, and the climb up is short — twenty minutes — with a sweeping view over Kerman and the surrounding plain from the top.
Best visited in late afternoon, when the heat has dropped and the light favours the brown earth of the citadel walls. The nearby Qaleh Dokhtar ("Maiden's Castle"), on a separate hill, is part of the same defensive system and can be combined into a longer walk. Wear proper shoes; the path is rough.