Band-e Kaisar

Band-e Kaisar
Remains of the dam bridge
Coordinates	32°03′14″N 48°50′55″E / 32.0538°N 48.8485°E / 32.0538; 48.8485
Carried	Sassanid road Pasargadae−Ctesiphon
Crossed	Karun river
Locale	Shushtar, Iran
Other name(s)	Pol-e Kaisar, Bridge of Valerian, Shadirwan
Characteristics
Design	Weir with bridge superstructure
Material	Sandstone ashlar, Roman concrete
Total length	Ca. 500 m
Longest span	9 m
No. of spans	40+
History
Designer	Roman engineers
Constructed by	Shapur I
Construction start	Ca. 260–270 AD
Collapsed	1885
UNESCO World Heritage Site
Official name	Shushtar Historical Hydraulic System
Type	Cultural
Criteria	i, ii, v
Designated	2009 (33rd session)
Reference no.	1315
Region	Asia-Pacific
Location

The Band-e Kaisar (Persian: بند قیصر, "Caesar's dam"), Pol-e Kaisar ("Caesar's bridge"), Bridge of Valerian or Shadirwan was an ancient arch bridge in the city of Shushtar, Khuzestan province, Iran, and the first in the country to combine it with a dam.^[1] Built by the Sassanids during the 3rd century CE, using Roman prisoners of war as the workforce,^[2] it is the easternmost example of Roman bridge design and Roman dam.^[3] Its dual-purpose design exerted a profound influence on Iranian civil engineering and was instrumental in developing Sassanid water management techniques.^[4]

The approximately 500m long overflow dam over the Karun, Iran's most effluent river, was the core structure of the Shushtar Historical Hydraulic System (سازه‌های آبی شوشتر) from which the city derived its agricultural productivity.^[5] The arched superstructure carried across the important road between Pasargadae and the Sassanid capital Ctesiphon.^[6] Repaired repeatedly throughout the Islamic period,^[7] the dam bridge remained in use until the late 19th century.^[8] In 2009, it was designated by UNESCO as Iran's 10th World Heritage Site.^[9]