Zendan-e Soleiman Iran

This dramatic 97m conical peak dominates the valley landscape for miles around. If you’re reasonably fit, climbing to the crater’s edge should take less than 15 minutes. The path is muddy but obvious, zigzagging up from the Takab road about 4km south of the main Takht-e Soleiman ruins. Though it’s now bare of all construction, the cone was once enclosed by fortified walls and topped by a religious sanctuary that archaeologists suggest dated to 900 BC. Zendan-e Soleiman means Solomon’s Prison, though anyone jailed within the central crater wouldn’t have lasted long, given the noxious sulphurous fumes – peering gingerly into its dizzying void can be suffocating enough.