GERDKŪH, a fortress on the summit of an isolated rocky hill in the Alborz mountains, situated some 18 km west of Dāmḡān (q.v.) in northern Persia. Thrust forward into a sloping plain, the hill of Gerdkūh rises about 300 meters above its base, and seen from the south, the access direction to the site, the hill appears dome shaped; hence its name Gerdkūh (round mountain). In medieval times, Gerdkūh was also known as Dež-e Gonbadān (q.v.), which Islamic sources have identified with the one mentioned in the Šāh-nāma (ed. Vullers, III, pp. 1550, 1552, 1635, 1643, 1671; Mojmal, p. 52; Rašīd-al-Dīn, 1959, p. 117; Mostawfī, Nozhat al-qolūb, text p. 161, tr. p. 158; idem, Tārīḵ-e gozīda, p. 93).

The date and circumstances of the construction of Gerdkūh, possibly a pre-Islamic site, remain unknown. The earliest known reference to Gerdkūh dates back to the early 4th/10th century in connection with the early Ismaʿili movement in the Jebāl. According to this, it was the residence of the Ismaʿili dāʿī ʿAbd-al-Malek Kawkabī, one of the immediate successors of the dāʿī Abū Ḥātem Rāzī (d. 322/934, q.v.; Neẓām al-Molk, p. 287; Rašīd-al-Dīn, 1959, p. 12). Later in the 5th/11th century, the fortress came into the possession of the local Saljuq amirs in Dāmḡān (Ebn al-Aṯīr, Beirut, X, p. 38). From the end of the 5th/11th cenutry until the middle of the 7th/13th century, the history of Gerdkūh is closely connected with the history of the Nezārī Ismaʿili state of Persia during the Alamūt period (Daftary, pp. 343-44, 363, 365, 367, 381, 414, 421-22, 425, 428-29).

Gerdkūh was placed at the disposal of Ḥasan Ṣabbāḥ, the founder of the Nezārī Ismaʿili movement in Persia, by Raʾīs Moʾayyad-al-Dīn Moẓaffar b. Aḥmad Mostawfī, around the year 493/1100. RaʾīsMoẓaffar, a secret Ismaʿili convert in the service of the Saljuqs, had earlier persuaded his superior Saljuq amir, Amīrdād Ḥabašī, to acquire Gerdkūh from Sultan Barkīāroq (q.v.) and to install him there as his lieutenant. Barkīāroq granted the request in 489/1096 and Ḥabašī appointed Raʾīs Moẓaffar as his lieutenant there. Raʾīs Moẓaffar, still posing as a loyal Saljuq officer, reconstructed Gerdkūh, making it as self-sufficient and impregnable as possible (Jovaynī, ed. Qazvīnī, III, pp. 207-08, tr. Boyle, II, pp. 678-79; Rašīd-al-Dīn, 1959, pp. 116-20; Kāšānī, pp. 151-55). It was a strongly fortified castle with ample water and food storage facilities, capable of withstanding long sieges, when it came into the possession of the Nezārī Ismaʿilis. Raʾīs Moẓaffar served as the Nezārī commandant of Gerdkūh for a long time and was succeeded by his son Šaraf-al-Dīn Moḥammad.

Situated strategically along the Khorasan road, and guarding the eastern approaches to the Alborz mountains and the Caspian highlands, Gerdkūh served as the most important Nezārī stronghold in Qūmes, one of the main scattered territories of the Nezārī state in Persia. At various times, the Nezārīs also levied tolls on travelers passing Gerdkūh (Jovaynī, ed. Qazvīnī, III, pp. 213-14, tr. Boyle, II, pp. 681-82; Rašīd-al-Dīn, 1959, p. 123; Kāšānī, p. 144). Gerdkūh became the last Nezārī stronghold in Persia to surrender to the Mongols. The fortress was besieged for seventeen consecutive years, starting in Rabīʿ I 651/May 1253. The garrison of Gerdkūh finally surrendered for the want of clothing in Rabīʿ II 669/December 1270, some thirteen years after the fall of Alamūt. The Mongols did not demolish Gerdkūh, as in the case of some other major Nezārī fortresses in Persia (Rašīd-al-Dīn, Tārīḵ-e ḡāzānī, 1940, pp. 30, 56; idem, Tārīḵ-e ḡāzānī, 1941, p. 29; idem, Jāmeʿ al-tawārīḵ, Baku, III, pp. 35-36, 140, 272, 286-87; Jūzjānī, II, p. 186). Gerdkūh was still in use in 786/1384 (Yazdī, I, pp. 280-82), but there is no mention of it in later sources. It seems to have been completely abandoned by the time of the early Safavids. The ruins of the living quarters built by the besieging Mongols and the two different types of the mangonel stones, used by the Nezārīs and the Mongols, are still scattered on the northeastern slope of the hill (visited by the present writer in 1985).

Of the major Nezārī fortresses in Persia, Gerdkūh is the one least studied in modern times. No archeological survey has been made of the extensive ruins and fortifications which exist on the summit and along the sides of the hill, and of the three outer walls of the site. Eʿtemād-al-Salṭana, who visited Gerdkūh in 1300/1882-83, has left a brief description of its ruins (III, pp. 302-7).



Moḥammad-Ḥasan Khan Eʿtemād-al-Salṭana, Maṭlaʿ al-šams, Tehran, 1301-3/1883-86.

F. Daftary, The Ismāʿīlīs: Their History and Doctrines, Cambridge, 1990.

Ferdowsī, Šāh-nāma III, ed. J. A. Vullers, Leiden, 1884.

M. G. S. Hodgson, The Order of Assassins, The Hague, 1955.

Haṟmd-Allāh Mostawfī, Tārīḵ-e gozīda, ed. ʿA.-Ḥ Navāʾī, Tehran, 1339 Š./1960.

W. Ivanow, “Some Ismaili Strongholds in Persia,” Islamic Culture 12, 1938, pp. 392-96.

Abu’l-Qāsem ʿAbd-Allāh Kāšānī, Zobdat al-tawārīḵ. Tārīḵ-e Esmāʿīlīya, ed. M.-T. Dānešpažūh, 2nd ed., Tehran, 1366 Š./1987.

Neẓām-al-Molk, Sīar al-molūk (Sīāsat-nāma), ed. H. Darke, 2nd ed., Tehran, 1347 Š./1968.

Rašīd-al-Dīn Fażl-Allāh, Jāmeʿ al-tawārīḵ: Qesmat-eEsmāʿīlīān, ed. M.-T. Dānešpažūh and M. Modarresī Zanjānī, Tehran, 1338 Š./1959.

Idem, Tārīḵ-e mobārak-e ḡāzānī, ed. K. Jahn, London, 1940.

Idem, Tārīḵ-e mobārak-e ḡāzānī. Dar dāstān-e Abāḡā Ḵān, ed. K. Jahn, Prague, 1941.

M. Sotūda, Qelāʿ-e Esmāʿīlīya, Tehran, 1345 Š./1966, pp. 142-60.

Yāqūt, Boldān, s.v. “Dāmḡān.” Šaraf al-Dīn ʿAlī Yazdī, Ẓafar-nāma, ed. M. ʿAbbāsī, 2 vols., Tehran, 1336 Š./1957.

(Farhad Daftary)

Originally Published: December 15, 2001

Last Updated: February 7, 2012

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