Suomenlinna Island Fortress is a group of islands just outside Helsinki, originally developed in the 18th century during the Swedish era into a naval fortress. Still during the Russian era in the beginning of the 19th century, it had a larger population than the city of Helsinki itself. Suomenlinna is now a UNESCO world heritage site.

The new building is an extension of an old depot building built in 1915. The extension recreates the original mass of the building by using exactly the original footprint as well as identical eaves and ridge heights. In order to maintain the sequence of historical layers the materials and techniques used, as well as the proportions of the fenestration, will, however, be contemporary in character. From further away the building will look as if it’s always stood there but while approaching it one gradually realizes that it is in fact new. The building will contain various functions related to the building activities on the islands.