Russia wanted to build fortress in the Finnish Gulf according to the Dutch magazine Marineblad dated 1910-1911 no. 11

An item reported that the Russian commission for defence proposed the founding of 2 fortresses in the Finnish Gulf. One near Reval [nowadays Tallinn, Estonia] and the second one on an island. The first fortress was to be fitted out with 170 guns included 20-30,5cm guns. With both fortresses was the defence of St. Petersburg, Russia completed and could the Finnish Gulf be blockaded against an attacking enemy.