- When one looks at the Hanko Cape area and especially how the borderline goes, you'll notice that in the area of Sommarö, the borderline of the rental area starts to curve away from the defensive line. When moving towards east in the defensive line, the distance from the borderline grows constantly. This affects to the relatively small number of fortifications in the Sommarö area and in the areas east from Sommarö.

- The west side of Sommarö however has had a significant role during the war. Together with the Odensö area, the fortifications in the west side have blocked the shortest route from the rental area to the mainland in the east side of Hanko Cape. Because of this, nearly all of the positions in the west side of Sommarö, which are aimed towards the channel coming from north-west, are either completely or partly constructed.

- From the west side fortifications the number 439 is interesting and unique in the Harparskog-line. The structure is a completely ready machine gun nest. There is a visible depression from the mounting for the machine gun in the structure wall. What makes this structure unique is the way it has been constructed. According to the map symbol the structure would have been a machine gun bunker/dugout, but the ready structure looks more of a machine gun nest. This structure has protected the foreground of the gun position 47, a & b. Structure 440/449 has been constructed for a similar task in the eastern side of the area. It has protected the foreground of the gun position 48.

- From the two gun positions, the structure 47, a & b, is in better condition. The position can be found right next to the Sommarö marina. If this position would be renovated, it could be a rather interesting tourist sight in the area. The second gun position in the area unfortunately has been filled completely. The structure was mined and at least in 1955 the structure has been visible.

- Nearby is also the observation and fire control nest 476. This is the best constructed observation and fire control nest in the whole Harparskog-line. The structure has been mined to a rock. Water however covers it now. Together these three previously mentioned structures would make a rather interesting tourist sight in the area. Renovating the positions probably wouldn't be a too hard task if you exclude the structure 48 from the renovating effort.

- Anti-tank obstacle lines have been drawn in the map, to a several locations in the shoreline. However it is not possible to confirm anymore whether or not these obstacles were build. A lot new has been built in the area during the past sixty years, which has affected to the surroundings. The eastern side of the area is nearly completely free from houses and roads, but it seems that not much was constructed there when it comes to fortifications.

- My own personal notes below are based on the situation in the defensive line, during the years 2005 and 2006.