After having been defeated in the Crimean War, Russia began an efficient reform programme to modernise its army, navy and fortresses. Reforms were also extended to Viapori, where new walls were built and modern coastal cannons were stationed starting in the 1860s.

 

A bastion fortress becoming outdated

 

Before the Crimean War, fought between 1853 and 1856, the Russians did little to modernise the bastion fortifications in Viapori which dated back to the Swedish era, although considered outdated. During the war, simple cannon batteries had been hastily built in front of and at the flanks of the central fortress. The parapet of the batteries comprised a earthen wall six to nine metres in thickness, with embrasures carved for guns.

 

Wood was replaced with iron and steel as construction material for vessels. Starting in the 1870s, the armour of warships was significantly improved. Sailing ships were replaced with steam-powered battleships equipped with breech-loading, rifled cannons. Their range and accuracy was considerably better than that of smoothbore muzzleloaded cannons, which was the kind of artillery that was stationed in Viapori.

 

Walls and coastal cannons

 

Extensive reforms began in 1859, continuing until the late 1870s. The focus of reforms was initially on the islands of Kuninkaansaari, Santahamina and Vallinsaari, which was located next to the island of Kustaanmiekka and in which three casemated batteries were built between 1859 and 1863. The parapet of the cannon batteries in the islands of Kustaanmiekka, Susisaari and Länsi-Mustasaari was reinforced with granite, and the thickness of the earthen wall was extended to around ten metres. Between 1866 and 1871, 25 gunpowder magazines and ammunition storages made of stone and brick were built behind the batteries. On top of the gunpowder magazine with the highest elevation behind each battery, a structure referred to as a pavilion for rangefinder equipment was built.

 

In the islands of Kustaanmiekka, Susisaari and Länsi-Mustasaari, modern 9 or 11-inch coastal cannons were placed in the 1870s. These cannons had been built either by Krupp in Germany or by the Obuhov arsenal in St. Petersburg or the Perm arsenal under license. The cannons were placed so that they formed batteries of two to four heavy guns protected by earthen walls. Their semicircle foundations were made of granite, and their firing sector was from 90 to 140 degrees. The cannons were bolted to their carriages, with their rear ends moving along rails. Heavy shells were lifted by means of a hoist attached to the carriage. In the 1880s, the foundations of the cannons were cast in concrete. Heavy shells were moved from ammunition storages to an area behind the batteries using a steam-powered engine.

 

After the Crimean War, fortifications were also built in the island of Vallinsaari, located next to Viapori, where new casemated batteries were built between 1859 and 1863. The construction of fortifications continued until the early 1900s. More than 20 gunpowder magazines were built in Vallinsaari and the adjacent island of Kuninkaansaari, in which the ammunition of Viapori was stored.