This wild-looking, incredibly eroded, cave-ridden mesa soars above (or, more accurately, falls into) the Qezel Owzan river in the ribbed and riven badlands 120km northwest of Zanjan. Reduced to a collection of tottering hollow hoodoos, the mesa's human-made caves were part of a Sassanid-era fortress. You'll need a full day's car hire from Zanjan to explore the area properly. The closest town is Mahneshan, 14km to the north.
The whole area is riddled with hoodoos. Ten kilometres before the castle, keep an eye out for Doodesh-e-Jen (Jinn's Chimney), a singular phallus-like tower.
