Suomenlinna Sea Fortress was built over 250 years ago and soon gained a population of 4600, larger than the population of Helsinki at the time. Its construction began in 1748, when Finland was part of the Swedish Empire and a young Swedish lieutenant colonel by the name of Augustin Ehrensvard came to Finland to direct the operations. The Swedes built a fortress on the islands as a counter to the increasing Russian naval strength in Kronstadt. The fortress was originally called Sveaborg - literally, Sweden's Fortress. In 1808, the fortress surrendered to the Russians, with Finland becoming part of the Russian Empire. During the Crimean War of 1854-56 Suomenlinna was badly damaged. After the extensive restoration work the fortress and its surrounding islands became a part of "Peter the Great's naval fortification" designed to safeguard the capital, St. Petersburg. The Russians ruled here for 110 years. Barracks, hospitals and a church were built for the needs of a big garrison. It was because of the fortress that Helsinki was chosen the new capital of Finland.
In 1918 after Finland finally gained independence from Russia, the fortress was renamed Suomelinna (Finland's Fortress). Today, it is an integral part of the city and home to around 900 inhabitants. Suomenlinna has always been much more than just a part of Helsinki - it is a city within a city and a unique place, which combines the museums with the place, where people live and work.
At present, the islands have a library, a health center, a shop, a fire brigade, and an elementary school. A reminder of the military past is the Naval Academy on Pikku Mustasaari Island. Its main building was designed by C. L. Engel, who also created the old neoclassical center of Helsinki.
There are a variety of attractions on the islands including the Suomenlinna Museum (with the Suomenlinna Experience multi-media show), the Ehrensv?rd Museum, the Doll and Toy Museum, the Manege Military Museum, Submarine Vesikko, the Coast Artillery Museum and the Customs Museum, so the tourist interest to the Suomenlinna is guaranteed.