The clearing work at the ruined Svartholma was begun in the 1930ies and since the 1960ies the Finnish Heritage Agency has maintained and restored the fortress. The western curtain wall of the fortress was emptied in the 1990ies and a roof of steel and wood was erected to protect the remains. The curtain wall had about three metres of sand, pieces of bricks and other debris. When the curtain wall was emptied the remains of an oven where also found. There was a bakery and kitchen, a physician’s apartment, pharmacy and clinic and living quarters for the men in the western curtain wall. Upstairs on the second floor there was a provisional church. A spiral staircase led to the second floor. The cobble stone areas of the inner yard were excavated and repaired in the summer of 1997.
Originally the curtain walls were two floors high, but during the Russian period a third floor was built in all curtain walls except the southern. In the southern curtain wall, where the commandant of the fortress lived, there was also a spiral staircase of similar kind. A safe holding the cash of the fortress was kept behind the staircase.
The 250th anniversary of the Svartholma sea fortress has celebrated in 1998. In celebration of this an exhibit in cooperation with the City of Loviisa and the Finnish Heritage Agency, as well as a summer café built in the style of a Russian warehouse building were opened.