Mount Khwaja or Mount Khwajeh is a flat-topped black basalt hill rising up as an island in the middle of Lake Hamun , in the Iranian province of Sistan and Baluchestan .
The trapezoid-shaped basalt lava outcropping , located 30 km southwest of the town of Zabol , rises to 609 meters above sea level and has a diameter ranging from 2.0 to 2.5 kilometres . It is the only natural height in the Sistan area , and is named after an Islamic pilgrimage site on the hill : the tomb and shrine of Khwaja Ali Mahdi , a descendant of Ali ibn Abi Talib .
Mount Khwaja is also an important archaeological site : On the southern promontory of the eastern slope , the ruins of a citadel complex - known as the Ghagha-Shahr - with its remains of a fire temple attest to the importance of the island in pre-Islamic Iran . According to Zoroastrian legend , Lake Hamun is the keeper of Zoroaster's seed . In Zoroastrian eschatology , when the final renovation of the world is near , maidens will enter the lake and then give birth to the saoshyans , the saviours of humankind .
The fire temple is on a terrace behind high walls and is protected by two forts , whose remains are respectively known as Kok-e Zal and Chehel Dokhtaran . Collectively , the ruins are called Qal'a-e Kafaran "Fort of Infidels" or Qal'a-e Sam "Fort of Sam ," the grandfather of the mythical Rostam (one of the fortresses here is named "Rostams castle") . Both names reflect pre-Islamic heritage . The walls of the temple were once extravagantly decorated with murals , some of which are now on display in museums in Tehran , Berlin , New Delhi and New York .
The citadel complex was first investigated by Marc Aurel Stein in 1915-1916 . The site was later excavated by Ernst Herzfeld , and was again investigated in part by Giorgio Gullini in a short expedition of 1960 . Initially , Herzfeld tentatively dated the palace complex to the 1st century CE , that is , to the Arsacid period (248 BCE-224 CE) . Herzfeld later revised his estimate to a later date and today the Sassanid period (224-651 CE) is usually considered to be more likely . Three bas-reliefs on the outer walls that depict riders and horses are attributed to this later period . Beyond the citadel at the top of the plateau are several other unrelated buildings , of uncertain function and probably dating to the Islamic period .
