In the second half of the 19th century, the access road to the Kronstadt Steamship Plant (now the Marine Plant) was paved with cobblestones. The plant was a "strategic facility" and stood at the origins of armored shipbuilding in Russia. The cobblestone pavement quickly deteriorated due to heavy traffic and constant transportation of heavy loads. The damp, rainy climate did not favor the preservation of the cobblestone pavement. Rain, snow, ice, and high groundwater levels destroyed the cobblestone pavement practically throughout the year.

In 1858, during one of his trips to America, the manager of the Kronstadt Steamship Plant, Alexander Sokolov, noticed the pavements arranged in New York and Boston based on the idea of engineer Knapp.

They had an original covering made of cast iron pieces shaped like tiles. This idea interested the head of the Steamship Plant, and upon returning home, he ordered the casting of cast iron tiles in the newly established foundry workshop at the plant, based on the samples they brought. Incidentally, Alexander Sokolov improved the design of the pavement elements. The tiles gained stops and recesses that interlocked, turning the pavement into a kind of chainmail. These tiles were experimentally used to pave the plant’s courtyard. The experiment was successful.

In 1860, Grand Duke Konstantin ordered the head of the construction department of the Kronstadt port, engineer lieutenant colonel Eyler, to test the cast iron pavement on a larger scale and in a location with heavy traffic. A site 160 meters long and 6.4 meters wide was chosen near the Hemp Bridge, along the fence of the new Admiralty.

Eyler argued that in terms of quality, it surpassed all known pavements in Russia and Europe, and despite the apparent high cost of installation (each square sazhen of pavement then cost 38 silver rubles), it was probably the most economically advantageous due to its durability.

From a technological standpoint, the paving was done as follows. The entire area allocated for it was excavated, the pit was compacted and filled with granite rubble about 15 centimeters thick, which was tightly rolled. The roadbed was bordered with large cobblestones. Cast iron tiles were laid on this prepared bed. After installing and interlocking the tiles with their teeth, the gaps both within the tiles and between them were filled with granite rubble and then thoroughly compacted. This created a solid mass of a smooth road surface. The physical wear of such a surface was barely noticeable; only periodic renewal of the granite covering was required.

Despite the relatively high specific costs, the new urban pavement gained a considerable number of supporters. In particular, engineer colonel Eyler, under whose supervision the pavement was constructed, noted: "Of all the pavements existing to date, both in Russia and throughout Europe, the cast iron pavement installed in 1860 in Kronstadt is undoubtedly the best, and although at first glance such road construction seems quite expensive, upon examining its strength and comparing it with other pavements, one is convinced that cast iron pavement is probably the most economically advantageous."

After the cast iron tiles successfully withstood the harsh winter of 1860-1861, it was decided to similarly pave several more Kronstadt streets, which were successfully used until the beginning of the Great Patriotic War.

In 1862, the cast iron pavement was installed under the St. Petersburg gates and along Petrovskaya Street; in 1863, along Bolshaya Ekaterininskaya Street; in 1864, from the Steamship Plant to the rampart and along the newly laid road at the Dock Admiralty. Twenty years later, in 1884, when the idea arose to install cast iron pavement in the St. Petersburg Arsenal, an inquiry was sent to Kronstadt about the condition of the metal pavements there. The reply stated that they "have never been repaired since their installation and are in good condition." In total, from 1861 to 1866, more than three kilometers of streets and roads in Kronstadt were paved with cast iron. They served the city without repairs for about 80 years.

In September 1941, an order came from Moscow to Leningrad to cast one million mine bodies. Of this amount, 70 thousand were assigned to the Kronstadt Marine Plant. Difficulties in sourcing raw materials forced attention to be turned to the old cast iron tiles.

Thus, only two small pieces of this pavement remain today on the Hemp Bridge and along the fence of the Petrovsky Admiralty on Yakornaya Square. In America, cast iron pavements in Chicago and Detroit were also dismantled during World War II. In the post-war period, cast iron pavements were lost in other American cities, including New York and Boston. The Kronstadt cast iron pavement represents a unique example of 19th-century road construction. It is probably the only cast iron pavement in the world preserved to this day. Samples of the tiles, transferred during the restoration of Yakornaya Square, can be seen at the Kronstadt History Museum.

Source:

https://xn--80aiqmelqc4c.xn--p1ai/press/news/istoriya-chugunnoj-naberezhnoj-v-kronshtadte/
Kronstadt History Museum

https://a-121.ru/chugunnye-kruzheva-kronshtadtskix-mostovyx/

https://cont.ws/@metafor/1461495

https://www.scientificamerican.com/article/terrys-cast-iron-pavement/