Both Bolærne and Rauer Coastal Fortresses were fighting the German invasion-fleet late 8th and 9th of April 1940. They didn't manage to sink any of the large German Cruisers like Blücher which was hit and sunk by Oscarsborg and Kopås Coastal Fortresses in the inner Oslofjord a little later that night. Rauer eventually had to give up the fight during the 9th of April after several skirmishes with German landing parties. Bolærne capitulated during the 10th of April after all it's guns had been destroyed by German aerial attacks. The German forces tried to land infantry by boats on to Bolærne too but met too much resistance, and therefore used aircrafts instead. As long as the main arnaments were active northbound German ships had to turn and go back south again. Bolærne Coastal Fortress lacked anti aircraft guns and was heavily bombed by German aircrafts and finally had to give up as none of the guns was functioning anymore.
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| This is how ChatGPT imagine the German aerial attacks on Bolærne |
Only one Norwegian was killed during the fightings of Bolærne. This small resistance delayed the German operation by 2 and a half day, enough to get the Royal family evacuated and start the Norwegian mobilization.
My Grandfather on my Mother's side, Ola Stein, was conscripted to serve with the Norwegian Coastal Artillery and was stationed on Bolærne Coastal Fortress during the battle of Norway in April 1940. The crew was not full, and there were only about 50 - 60 Norwegians to man Bolærne Coastal Fortress. I don't know what he was serving as, because he never talked much about the war. Actually he was on this Fortress when my mother was born on the 10th of April 1940 on their home island further south, Hvasser. The Norwegian soldiers were discharged when the German forces eventually landed on Bolærne, so my Grandfather went home to Hvasser and his newborn daughter. There he teamed up with his brother in law, my Granduncle Bertram, and joined the Norwegian Resistance Movement for the rest of the war.
Bolærne Coastal Fortress went out of active duty in 2001, and opened to the public in 2004 after bunkers was bricked up and trenches filled in for public safety. This year I decided to take the ferry out to Eastern Bolærne to have a look at this heavily fortified island and where my Grandfather served during the battle of Norway.
Since Bolærne Coastal Fortress was established in 1916, and later developed during WW2 and the Cold War, it's a really mix of old and new positions, bunkers and emplacements scattered around the island. Lessons learned by WW2 the post war fortress defense works was very elaborate, guarded by heavy armed infantry in heavily fortified positions, with mortars, heavy machine guns, anti tank weapons and AA-guns in addition to more modern and better coastal guns off course. The different AA-guns could also be used to engage smaller vessels.
This is a mortar position among several similar ones:
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| There was no mortar in it, this is just a photo from the museum what they used to look like when ready |
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| 3 NCOs could live and operate the Command nunker for a really long time. |
When taking a guided tour you can also take a look inside some of the bunkers. It was really interesting to see what these semi automatic 'modern' turret guns where hiding 6 meter below:
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| An ammo store to load the rapid firing gun. It could fire 20 shells a minute |
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| Each gun was manned by 3 NCOs... |
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| ...and 12 privates who could live in the gun for a longer period. |
The tunnel/mountain batteries was established in 1916 and upgraded during WW2 and the Cold War:
This tank was painted on the side of a nearby islet and served as a target for shooting practice with anti-tank weapons:
My accommodation for the night:
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| At least I have 'Sea-view' |
It's also a museum at the island which is open some few days after week during the summer. I relly advice to take their guided tour:
On Bolærne I also found some rails. There has never been any trains there though. The first short (standard gauge) rail I found was to move the searchlight around from the older part of the fortress:
Although none of these rails were served by trains or a locomotive, it sure makes your imagination spinn. Especially for a railway modeller. Of the more than 400 German Coastal Fortresses in Norway during WW2, some of them actually had narrow gauge railways during construction or to transport supplies and munitions to the guns or ships. It would most certainly be a interesting theme for a model railway layout.
Thank you Grandfather for your service!























































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