LANBASAR (the form in Rašid-al-Din and Ḥamd-Allāh Mostawfi; popular pronunciation, and the form used by Jovayni, Lam(m)asar), an important fortress of the Nezāri Ismaʿilis in the valley of the Šāhrud river, a tributary of the Safidrud, in the mountainous district of Rudbār, within the region of medieval Islamic Daylam in northwestern Iran.  Its precise location is in the valley of the Šāhrud’s minor affluent, the Nāyinrud, just off the main river valley (lat 36o33′ N, long 50°13′ E; Mostawfi, pp. 60-61; tr., pp. 66-67; Le Strange, pp. 220-21; Krawulsky, pp. 276-77).  It protected the valley of Alamut from attacks; hence it was strategically important for the defense of the network of Ismaʿili strongholds in the region.  It had been seized, according to Jovayni (III, pp. 208-9; tr., II, p. 679), in 495/1102 from a local Daylami chief by the lieutenant and eventual successor of the Ismaʿili leader Ḥasan Ṣabbāḥ, Kiā Bozorg-Omid, who held it for the next twenty years until he became Ḥasan Ṣabbāḥ’s successor at Alamut. 

Lanbasar was visited by Freya Stark in 1931 (Stark, pp. 234-51) and Vladimir Ivanow in 1958 (Ivanow, pp. 60-74), both of whom left descriptions, but the most frequent visitor and author of the fullest descriptions has been Peter Willey (Willey, 1963 and 2005).  The site slopes at 30o and measures some 480 m by 190 m, with easily defensible surrounding slopes.  The outer walls of the fortress can be traced quite clearly, and within these are a main citadel and the remains of stables.  There is an extensive and complex water catchment system, with no fewer than fifteen cisterns dug into the rock plus a man-made channel or kāriz across the neck of land, linking the fortress site of Lanbasar with the adjacent main mountain mass, which would supplement in summer and autumn the rainwater collected within the cisterns during winter and spring; water could also be obtained from the Nāyinrud.  Willey estimates that these water supplies would have been sufficient for a garrison of 500 men and their horses and mules during hot summer months and were presumably adequate for the needs of the Ismaʿili defenders even during its year-long siege by the Mongols after the fall of Alamut to Hülegü’s troops in 654/1256 (see below; for detailed descriptions, see Willey, 1963, pp. 267-79; idem, 2005, pp. 128-33, with plans and illustrations).  In his campaign in northwestern Iran against the Ismaʿilis, the Saljuq sultan Moḥammad b. Malekšāh sent his commander Atābak Nuštegin against Lanbasar and Alamut. Labansar was besieged in 511/1117, but the attack failed to capture it and the siege had to be lifted when the sultan died (Jovayni, III, p. 212; tr., II, p. 681; cf. Willey, 2005, p. 129).  An attack by the troops of sultan Maḥmud b. Moḥammad some ten years later likewise failed (Hodgson, p. 102).  In the next century, the last Ismaʿili Grand Master, Rokn-al-Din Ḵoršāh (q.v.), submitted to Hülegü when the Mongols overran Iran and handed over some forty Ismaʿili strongholds.  Lanbasar, however, held out for a year until it surrendered to Hülegü’s general Dayer Buqā in 655/1257, but was presumably thereafter abandoned (Jovayni, III, pp. 268-74; tr., II, pp. 718-22; Hodgson  pp. 269-70; Daftary, 1990, pp. 428-29; Willey, 2005, p. 129).  


C. Edmund Bosworth, “Lanbasar” in EI2 V, 1986, p. 656.

Farhad Daftary, The Ismaʿilis: Their History and Doctrines, Cambridge, 1990; new ed., 2007, pp. 393-97.

Ḥamd-Allāh Mostawfi, Nozhat al-qolub, ed. and tr., Guy Le Strange, as The Geographical Part of the Nuzhat-al-Qolub, 2 vols., Leyden and London, 1915-18. 

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

Vladimir Ivanow, Alamut and Lamasar, Two Mediaeval Ismaili Strongholds in Iran: An Archaeological Study, Tehran, 1960.  

ʿAlāʾ-al-Din ʿAṭāmalek Jovayni, Tāriḵ-e jahāngošāy, ed. Moḥammad Qazvini, 3 vols., Leyden and London, 1912-37; tr. John Andrew Boyle, as The History of the World-Conqueror, 2 vols., Manchester, 1958.  

Dorothea Krawulsky, Iran, das Reich der Ilhane: eine topografisch-historische Studie, Wiesbaden, 1978.  

Guy Le Strange, The Lands of the Eastern Caliphate, New york, 1966; tr. Maḥmud ʿErfān, as Joḡrāfiā-ye tāriḵi-e sarzaminhā-ye ḵelāfat-e šarqi, Tehran, 1959.  Freya Stark, The Valleys of the Assassins, and Other Persian Travels, London, 1936.  

Peter J. E. Willey, The Castles of the Assassins, London, 1963.  

Idem, Eagle’s Nest: Ismaili Castles in Iran and Syria, London, 2005.

(C. Edmund Bosworth)

Originally Published: December 12, 2014

Last Updated: December 12, 2014

Cite this entry:

C. Edmund Bosworth, "LANBASAR,"  Encyclopædia Iranicaonline edition, 2014, available at (accessed on 12 December 2014).