Stock Press Photo | The Suomenlinna Sea Fortress

Suomenlinna (Sveaborg) is a sea fortress, which was built gradually from 1748 onwards on a group of islands belonging to the district of Helsinki. The work was supervised by the Swedish Admiral Augustin Eherensvärd (1710-1772), who adapted Vauban’s theories to the very special geographical features of the region. The landscape and the architecture of the fortress have been shaped by several historic events. It has served to defend three different sovereign states over the years: the Kingdom of Sweden, the Russian Empire and most recently the Republic of Finland.
Covering an area of 210 ha and consisting of 200 buildings and 6 km of defensive walls, the fortress stretches over six separate islands. The original fortress was built using local rock and fortified with a system of bastions over varied terrain. The purpose of the fortress was originally to defend the Kingdom of Sweden against the Russian Empire and to serve as a fortified army base, complete with a dry dock. Sandbanks, barracks and various other buildings were added during the 19th-century Russian period. The defensive system was adapted to match the requirements of a modern fortress and developed in the 19th century using contemporary fortification equipment.

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