Mir Bahaeddin Bridge

Mir Bahaeddin Bridge is one of the most important historical monuments of Zanjan. It crosses the Zanjanrud River at the start of the road from Zanjan to Bijar. This valuable bridge was built in the Qajar era, during the reign of Naser al-Din Shah, through the efforts of Haj Mir Bahaeddin Zanjani, a renowned philanthropist and notable of the city, and today it is regarded as one of the symbols of Zanjan's historical architecture. Also known as the Old Bridge (Pol-e Kohneh) and Ezhdahatu Bridge, it was registered on Iran's National Heritage list on 18 Mehr 1356 under number 1484. Because the bridge stands on the bank of the Zanjanrud and along the historical route linking Zanjan with the southern regions, it holds a special place in terms of history and connectivity as well as architecture.

Mir Bahaeddin Bridge is built of brick, with an approximate length of 100 metres and a width of about 6.7 metres, and is considered one of the most outstanding examples of Qajar-era bridge building in northwestern Iran. The bridge has three main spans with pointed arches, and the middle span is designed to be larger than the other two. On the inner face of the largest arch there is a beautiful inscription in Maqeli (square Kufic) script, bearing the date of the bridge's construction and the phrase «Ya Ali» set out symmetrically. The piers are made of cut stone and lime mortar, and to reduce the load on the structure, the builders designed the spaces beside the spans as hollow chambers. The two-storey niches above the piers not only lightened the building but also allowed floodwater to pass through. These features show the considerable engineering knowledge of the bridge's builders in the Qajar period.

Mir Bahaeddin Bridge lies in the southern part of Zanjan, next to Zanjanchay Park, and is easily reached via the Zanjan–Bijar road and the Khayyam ring road. While viewing this historical structure, visitors can also enjoy the green space along the river and the surrounding views. The best time to visit the bridge is spring and early autumn, when the flow of the Zanjanrud and the region's weather are at their most pleasant. Keeping the area around the bridge clean, avoiding damage to the historical parts of the structure and observing the principles of responsible tourism play an important role in preserving this valuable heritage for future generations.