The Blue Bridge in Saint Petersburg is the most inconspicuous landmark of the city. Many tourists and residents do not even realize that they have walked across it. Yet this structure has a deep historical past, including legends and beliefs.

Since 1737, there was a wooden drawbridge here, which got its name from the color it was painted. Later, it was rebuilt into a three-span bridge with a wooden superstructure on stone supports, modeled after the Kryukov Canal bridge. In 1818, according to Geste's design, the bridge was rebuilt into a single-span cast-iron arch. The superstructure was a two-hinged arch, structurally a solid vault. The construction was carried out by Geste’s successor, bridge builder Bazhen. The superstructure was assembled from cast-iron sections bolted together. The cast-iron parts were manufactured at the Olonets Cast Iron Foundry. The Blue Bridge’s abutments are massive stone structures on a pile foundation, faced with granite. Cast-iron railings were installed on the bridge.

The sidewalk was separated from the roadway by simple cast-iron railings with cast-iron pedestals. The facades of the superstructure featured several ornaments. The bridge’s surface was paved with stone. Initially, it was narrower, with a width of 41 meters.

In 1842-1843, due to the construction of the Mariinsky Palace and the redevelopment of Isaakiyevskaya Square, the bridge was widened upstream towards the Red Bridge to 97.3 meters. The superstructure was made of cast-iron tubings bolted together.

At the end of the 18th century, the square near the Blue Bridge was a kind of "labor exchange." Workers gathered here seeking employment: carpenters’ and masons’ cooperatives could be found in the square. Workers could be not only hired but also bought at the market. This place was popularly called the "slave market." This market existed until 1861.

Since 1925, cracks appeared in the cast-iron boxes of the vault on the downstream side, built in 1818. In 1929-1930, the cast-iron arches on the downstream side were replaced with reinforced concrete ones, while the old abutments were preserved. The superstructure is a two-hinged arch. The cast-iron part built in 1842 has survived to this day. In 1938, the stone pavement on the bridge was replaced with asphalt concrete.

In the 19th-20th centuries, the bridge was repeatedly reconstructed, its dimensions and structural features changed. Despite this, its appearance has not changed, and the external look of the crossing has reached us almost in its original form. The saying applies to the bridge, as well as to the nearby Mariinsky Palace, that two emperors turned away from it: the positions of the equestrian statues (The Bronze Horseman and the monument to Nicholas I) are directed away from the bridge.

The Blue Bridge, simple in architectural design, fits organically into the ensemble of the granite embankments of the Moika River. Nearby are the Mariinsky Palace, Isaakiyevskaya Square with the monument to Nicholas I, St. Isaac’s Cathedral, the buildings of the All-Russian Institute of Plant Industry named after N. I. Vavilov and its library, and close by — the Composer’s House. The Admiralty building can also be seen from the bridge. Initially, according to Geste’s design, granite obelisks were used as lanterns. Lanterns copying the lamps on the Alexander III Bridge in Paris were installed at the end of the 19th century. These lanterns remained on the bridge in their original form for a long time. The existing torcheres were restored during the 2013–2014 reconstruction, modeled after the torcheres of the Baltic Railway Station. In 1971, on the Moika embankment near the downstream side of the Blue Bridge, a granite post-footstock decorated with Neptune’s trident was installed according to architect Petrov’s design. The post bears marks of the water levels of the largest floods in Saint Petersburg: 1824, 1903, 1924, 1955, 1967. Saint Petersburg residents nicknamed it the "Neptune Scale."

From April 2013 to September 2014, a major overhaul of the bridge was carried out. The reinforced concrete vault was strengthened with additional reinforcement, a reinforced concrete relieving vault was constructed above the cast-iron part, the railing and cast-iron metal decor were restored. The power fence and torcheres were also recreated, the supports, granite cladding of the walls adjoining the supports to the embankment, and the cast-iron tubings were repaired. The riverbed was reinforced with concrete mats. Safety islands appeared on the bridge.

The Blue Bridge over the Moika River is the widest bridge in the world. It connects Kazansky and 2nd Admiralty Islands. Thanks to its record width, it has become a kind of "invisible bridge" — many perceive it not as a crossing over the Moika River but as part of the square. The Blue Bridge fits organically into the surrounding architectural ensemble with all its historic buildings and monuments. It is a single-span structure 29.4 meters long, with a width along the cornices of 95.4 meters, and a width along the parapets of 113.85 meters. The total area of the bridge deck is 2,294 square meters, with sidewalks covering 143 square meters.

The Blue Bridge’s superstructure is a hinge-free vault made of cast iron and reinforced concrete. The railings are cast iron, artistically cast, with a pattern repeating the design of the Moika River fence. The sidewalks are separated from the roadway by simple cast-iron railings. The bridge is part of the Isaakiyevskaya Square ensemble.

It is worth noting that the bridge is a popular parking spot for government officials of the executive authorities of Saint Petersburg and employees of the city Legislative Assembly, which is located in the Mariinsky Palace.

There is a myth that the bridge’s width is not 97.3 but 99.9 meters. This figure even appears in some historical textbooks about Saint Petersburg. Where this mythical number came from is unknown. It may be a symbolic rumor among residents or a careless typo. This persistent misconception arose after the bridge’s reconstruction in 1842. Another saying about the bridge is that two emperors turned away from it. Residents confirm this interesting fact by pointing out that the monument to Nicholas I and the statue of the Bronze Horseman face away from the Blue Bridge. It is also said that the Blue Bridge on Isaakiyevskaya Square helps to restore youth and strengthen health. One only needs to touch the colored railings and mentally ask for this. Whether this is true or not is hard to judge, but those who know claim that if you ask the bridge with a pure soul and sincerely believe in it, it will surely help.

Sources:

https://mostotrest-spb.ru/bridges/sinij

https://peterburg.ru/sights/siniy-most

https://www.citywalls.ru/house15794.html

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