Siosepol or Siose Bridge [ˈsiː oˈseh ˈpol] (Persian: سی و سه پل, which means 33 Bridge or the Bridge of 33 Arches), also called the Allah-Verdi Khan Bridge, is one of the eleven bridges of Isfahan, Iran and the longest bridge on Zayandeh River with the total length of 297.76 metres (976.9 ft). It is highly ranked as being one of the most famous examples of Safavid bridge design.
it was constructed by the finance and the inspection of Allahverdi Khan Undiladze chancellor of shah abbas I, an Iranian ethnic Georgian, it consists of two rows of 33 arches from either sides, left and right. There is a larger base plank at the start of the bridge where the Zayandeh River flows under it, supporting a tea house which nowadays is abandoned due to the shortage of water and the river drought.
other names for the bridge include (the bridge of 33 springs)(the bridge of chaharbagh), and finally (zayandeh river bridge)
Allāhverdi Khan Bridge. Already in 1596 when Shah ʿAbbās the Great`s campaign for the Čahārbāḡ Promenade had begun, the project anticipated the building of a bridge to connect the northern and southern stretches of the avenue as well as of the city as it were being developed for the residence of new social groups in Isfahan. .This need was materialized between 1011/1602 and 1015/1607 with the construction of the Allāhverdi Khan Bridge (popularly known as Si-o-seh pol “The bridge of thirty-three spans” and as Pol-e Si-o-seh čašma “The bridge of thirty-three arches;). Eskandar Beg Torkamān called it “A sublime bridge, consisting of forty vaulted arches of a special type that would open so that in time of floods the water would pass through each one of the arches, having been built to span the Zāyandarud,” and in the 19th century, Sir Percy Sykes described it as “even in decay must rank among the great bridges of the world” .
The bridge measures approximately 300 meters in length (388 yards according to Sykes, p. 201). Along its sides are thirty-three arches, giving the bridge its popular name of Si-o-seh Pol. The central lane of the bridge was designed as a path for beasts of burden while the sides were raised for use as pedestrian promenades. Along the walkway the arches form small pavilions, where passersby can rest in shade and take in views of the river and its banks. Until the 19th century, the interior was decorated with paintings (as was that of the Ḵᵛāju Bridge) of subjects often referred to by European travelers to have been erotic .
This magnificent feat of engineering facilitated linkage through the Čahārbāḡ between the royal precinct (the Dawlat-ḵāna) and the new inner city zones around the Meydān on the one hand, and the suburban palace retreat of Hazār Jarib and the southern suburbs on the other. In addition to connecting the mansions of the elite that lined the southern flank of the Čahārbāḡ, the bridge served to connect to the city the Armenian merchant enclave of New Julfa, an economically vital community incorporated into the household by Shah ʿAbbās the Great and his immediate successors.The mediatory role of the new elite of the reconfigured Safavid household is similarly exemplified through the surrogate patronage on behalf of Shah ʿAbbās the Great and the royal household, which Allāhverdi Khan (q.v.), the commander-in-chief of the armies, extended in this integral feature of the urban campaign.