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Saint Isaac's cathedral genius 25 000 piles innovation

Structure review

Saint Isaac's Cathedral

By Alex Florstein

General Info 📚

  • Location: Saint Isaac's Square 4, Saint Petersburg, Russia, 🇷🇺

  • Style: Late Neoclassical, Byzantine and Greek

  • Years of construction: 1818 to 1858, 40 years

  • Construction cost: 1 000 000 gold rubles

  • Total height: 101.52 m

  • Entrance to the cathedral: 250 rubles (it’s free for children under 7 years old, while children and young people from 7 to 18 years old must pay 50 rubles).

Design 🏗

It is the largest Orthodox cathedral in St. Petersburg – and the 4th largest in the world! (The tallest one is the People's Salvation Cathedral in Bucharest, Romania.)

The temple has a volume of 260 000 m3 and dimensions of 111.3 m x 97.6 m.

Designed and constructed by a French classicist architect Auguste de Montferrand. Emperor Nicholas, I personally oversaw its construction, showing the importance of this grand project. During the construction, Montferrand almost got killed (in November 1837), when the workers were lifting 64-ton dome columns to their full height. The architect fell from the scaffolds, but, luckily, nearby workers managed to catch him.

The scaffolding was made by Spanish engineer Agustin de Betancourt and the works were extended until 1858.

Auguste de Montferrand died just one month after the construction was completed. That was his last and, probably, the greatest creation...

Views from the top

During the construction in 1818, to ensure that the cathedral's structure will not sink and collapse into the fenland of Saint Petersburg, 25,000 piles were driven to strengthen the foundations of the structure. The costs of the foundations rose to 2.5 million rubles, which at the time made the cathedral the most expensive temple in Europe.

The cathedral's interior, on the other hand, was decorated with about 400kg of gold.

History 📑

Under the Soviet government, the building was stripped of religious trappings. In 1931, it was turned into the Museum of the History of Religion and Atheism, the dove sculpture was removed, and replaced by a Foucault pendulum.

In 1937, the museum was transformed into the museum of the cathedral that you visit nowadays.

During World War II, the dome was painted over in grey to avoid attracting attention from enemy aircraft. On its top, in the skylight, a geodesical intersection point was placed, to determine the positions of German artillery batteries.



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