- Hanko Cape and the surrounding area has been nearly always an important military object. The Gulf of Finland can be easily closed with coastal batteries located in Hanko Cape and in Paldiski, which is located in the Estonian coast. The distance between these two places is only 80 kilometers. The distance between Russarö which is close to Hanko and Osmussaar which is located quite close to Paldiski, is only some 60 kilometers. For this reason the area has always been an important place for Russia and before them, to the Swedes. The Hanko Cape also offers an excellent place to land forces and to advance quickly towards Helsinki and Turku. The last important factor is the fact that the Hanko harbour remains operational through out the year. All of these facts were proven to work during the First World War, when the Imperial Russia closed the gap between Hanko/Russarö and Paldiski/Osmussaar with their coastal batteries, thus preventing naval movements to Gulf of Finland and towards St. Petersburg.  After that came the Germans during the Finnish Civil War and landed to Hanko in April 1918 and advanced quickly to Helsinki. The more mobile and modern warfare and the fact that fixed coastal gun positions have become obsolete in this sense, haven't diminished the military importance of Hanko Cape.

- The issue of Hanko Cape was raised again to the table when Soviet Union presented territorial demands to Finland in the autumn of 1939. One of these demands was to rent Hanko and the surrounding area as a naval base for Soviet Union for thirty years. This was absolutely something, which Finland could not bend to accept. Renting a military base from the Finnish soil was out of the question. The Russians tried several times to change the planned rental area, but the Finnish answer was always strong no. If the issue of Hanko would have not been in the territorial demands, it might have been that Finland would have accepted the demands and there would have been no Winter War. For example J.K. Paasikivi who was a delegate in the negotiations held in Moscow, states in his memoirs that, he thought that Finland should have made few admissions with the Russians to avoid war. Also Mannerheim who knew quite well the state of the Finnish military, thought that Finland could have given up Jussarö instead of Hanko. The Russians and especially Stalin were frustrated with the Finnish delegates.

- At one point Stalin suggested that if Finland doesn't like a foreign military base in their soil, then the Russians would dig a channel through the Hanko Cape, so that the base would not be in the Finnish mainland. The negotiations however came to a fruitless end on 9th of November 1939 and on 30th of November the Winter War started with the well known results.

- As the Winter War came to an end on 13th of March 1940, Finland was forced to accept much harder territorial losses than what had been talked during the autumn of 1939. One of these territorial losses was the Hanko Cape and the surrounding islands. The area, which was rented to Soviet Union was a lot bigger, than the area which had been talked previously. The situation for Finland was now extremely dangerous and the Hanko Cape needed to be closed effectively from the Soviet base. The order for the defence of Hanko Section was given immediately after the Winter War on 15th of March 1940 and Colonel Lieutenant Kesämaa was appointed as its commander on 19th of March 1940.

- The borderline of the Soviet rental area of Hanko was so long and a difficult one to guard with the navy, that General Major Väinö Valve who was in charge of the navy, asked for more troops and a high ranking officer from the land forces to be put under his command in order to guard the borderline effectively. 13th Brigade was formed first to this task and later as the signs of war were approaching, 17th Division took the responsibility of guarding the borderline of the rental area. Additionally 4th Coastal Brigade and Frontier Guards were placed under the command of Valve. Together these troops formed the Hanko Group, which was established in June 1940 to oversee operational planning. Colonel Aarne Snellman commanded Hanko Group at first. Snellman held this task to the summer of 1941 after which the troops in Hanko Front were reorganized and at first Colonel Lieutenant Kesämaa was appointed as a commander of Hanko Group, but from August 1941 onwards the commander of Hanko Group was Colonel E.R. Koskimies. 

- The actual fortifying job was started quickly after the peace agreement. Captain Kuumola arrived to the area on 29th of March 1940, with the task of starting the fortification work. The main points, which were to be considered, were that the enemy now had a base, from which it could launch a surprise attack towards the strategic targets in Finland. Secondly, the defensive line should be as close as possible to the borderline of the Soviet rental area, as the further off the defensive line was build, the more longer it would be. If the distance of the line from the borderline would be 15 kilometers, then the whole length of the defensive line would be only 40 kilometers. But if instead the defensive line would be build 25 kilometers away from the borderline, the length of the defensive line would grow to 70 kilometers. Thirdly, the most important area was the Hanko Cape and constructing fortifications in that area, were top priority. The fourth and fifth points were about the troops in Hanko area where constant battle readiness should be maintained with the troops and that the field fortifications must be build at the same time with the permanent fortifications.

- Also as it was most likely that the main Soviet attack would happen in the eastern frontier, only limited amount of troops would be reserved for Hanko area. The defensive line was planned and build to the level of: Sommarö - Björnholmen - Skogby - Harparskog - Vitträsk - Storholmen - Bojnäset - Grundsund - Bredvik.

- It was assumed that the construction of the defensive line would cost some 70 to 100 million Finnish marks. The construction was started very quickly and most of the plans for different areas were ready already in the summer of 1940. During the winter much was made ready and Field Marshal Mannerheim visited also the area to see how the constructions were progressing. As the war started, the constructions in Hanko Cape area were nearly completed. The fortification work on the east and west side of Hanko Cape didn't really start until the spring of 1941 and so not much was completed in those areas. Still also in those areas, the field fortifications were build constantly. 

- When the Continuation War started, the troops in Hanko Group were divided into different sections. There were six different sections: Section Hiittinen, Section Bromarv, Section Prästkulla, Section Hanko Cape, Section Snappertuna and Section Inkoo. Harparskog-line was too far away from the borderline of the Soviet rental area that it really couldn't affect to the immediate actions there. Also the Finnish troops nearly immediately when the war had started, moved to the advanced positions in the level of: Porsö - Storholmen - Möön - Prästö - Lackisår - Kamsholmen - Nästräsk - Lappvik - Järnö - Björholmen - Danskog - Elgö. Harparskog-line was left rather far away from the advanced positions. Still as the line was a sturdy one, it enabled to move troops to the Eastern Front, which was done in July to August 1941. The defensive line also discouraged the Russians to try an attack against the Finnish lines. A weak defensive system might have encouraged the Russians to try an attack in the Hanko Cape area. The defensive line also gave an opportunity to the Finnish engineers to practice how to assault fortified positions.

- The fortification report from 31st of May 1941 states that there was 46 concrete bunkers ready in the line and another 141 were under construction. Additionally some 113 open machine gun positions had been build along with a 29 positions for anti-tank guns. 12 machine gun positions were still under construction. 70 artillery positions and 17 fire control positions were completed and another 12 artillery positions were under construction. 46 dugouts were ready and 13 under construction. 57,8 kilometers of barbed wire obstacles had been build. For the anti-tank obstacles the figure is an interesting one, as it states that only 3,8 kilometers of anti-tank obstacles was ready and only 1,5 kilometers was under construction. If the figure is correct, then it means that the rest of the anti-tank obstacles were constructed quite quickly during the summer and autumn of 1941 as the obstacle line stretches through the Hanko Cape. The length of the line here is a bit over 9 kilometers and as the Hanko Cape area isn't the only one where anti-tank obstacles were build, the figure from the fortification report is a very low one. 

- When the Continuation War ended, the meaning of Harparskog-line ended too, as Soviet Union didn't want Hanko Cape anymore. Instead Finland was forced to rent the Porkkala Cape to Soviet Union. From the Porkkala Cape, the Soviet artillery could have bombarded even the Finnish Parliament building in Helsinki.

- Today the Harparskog-line, which still is in excellent condition, sleeps in the forest, nearly forgotten, with only few memorials reminding people the meaning of Hanko Cape and the surrounding area during the Second World War. Entering to the bunkers, you enter to the aftermath of Winter War. Hopefully you'll enjoy and appreciate your visit to the Harparskog-line through this presentation. It is a defensive line, which is overlooked in literature. There are several books about Salpa-line which protected the eastern frontier, but not a single one from Harparskog-line.