Saturday, October 21, 2017


The flights from Sweden were incredibly booked this week, so I ended up in returning home on an airline that I've never heard of before, 2N or Nextjet. And interesting routing, via Port. And there was an interesting rust on the airplane...

But we made it to Helsinki :-) and it was interesting to land to an airport that was covered by a thin layer of fog in the night.

Photos (c) 2017 by Jari Arkko. All rights reserved.

Friday, October 20, 2017


On the way back to the airport and home, I stopped at the yet another place on the Korvlinjen, this time in Arninge, a village in Täby. There was supposed to be two fortresses or bunkers here. I found one fortress, but could not get in, and did not find the other one.

Västrä Arningefortet is maintained by the landowner, and in reasonable condition. But, unfortunately it also locked and impossible to enter. Sad. Östrä fortet was supposed to be a half-collapsed structure, but by now I was starting to run out of the 20 minutes I had for the stop in Arninge, and would soon have to get to the airport and start my conference calls. I kept crisscrossing the thick forest, but found nothing, except a trench. I must have been close, but the almost impenetrable forest perhaps kept me from finding the actual bunker.

I also had not taken proper GPS coordinates, but was going simply on the rough direction from an inaccurate map and the Google Maps indication of "Systembolaget" in the forest where the fortress was supposed to be. I figured the local winos are perhaps camping out in the bunker, and have given it a name... but no, nothing on those coordinates. Odd.

The actual coordinates for the Västrä fortress are: N 59.463344 E 18.124656 and for the trench that I found for the Östra fortress: N 59.459962 E 18.132322.

More photos of the Västrä fortress:

The trench that I found around the Östra fortress:

The Uber taxi waiting for me near the Östra fortress:

Photos (c) 2017 by Jari Arkko. All rights reserved.

100 Articles!

The 2nd Korvlinjen article was the 100th blog article I've written this year. Quite a number. I've attempted to do more explorations, often local things like caves and abandoned bunkers or interesting swimming pools, in addition to the usual skiing articles.

I'm trying to run this blog as a journal of my adventures, whatever they may be, and this month I've succeeded in writing something almost every day. And the change in the work that I do has also enabled me to have a bit more reasonable working hours since April, so I do have some free time in the evenings to go do some things. That's good.

Incidentally, with the publication of *this* article the count is now 101 :-)

Photos (c) 2017 by Jari Arkko. All rights reserved.

Thursday, October 19, 2017

Mera Korv!

Mera korv, more sausage? Once again I'm in Kista, but wanted a quick outing in the evening after a long day. The answer was once again Uber to another bunker on the Korvlinjen.

Only this time the darkness fell earlier, and I made a mistake in leaving my computer power supply to the office. While I sprang from the taxi to office to fetch it, more minutes passed. When we arrived at the Prästgården village near the bunker, it was already dark.

I did have (one) flashlight, however, so took that out and set out in the forest. Fortunately, there was a path, and it did lead to the bunker.

And the door was open. Quite inviting, unlike back home in Finland where the bunkers from Russian occupation have been blown up. The sensible swedes have stayed out wars for couple of hundred years, so these bunkers have only been damaged by time...

... and skaters and tag-painters. Wood planks had been setup throughout the bunker to act, I guess, as skating platforms. And the whole inside was painted in one way or the other.

While the taxi was waiting, I quickly took a few photographs, made sure I had walked through the entire structure (I think), and headed back. Another day, another bunker. If you want to visit, take a look at the map of Korvlinjen's remains.

By the way, my underground adventures have been listed on the map at (there's also a more traditional listing). The map makes it possible to look at various locations, and by clicking on the pins on the map, you'll get to the article about that location. There's also a similar page at I have plans to add more features, like menus to choose articles on places where there's more than one article about the same location, pointers to cave maps, etc.

Note that in Sweden some of the cave locations on the map have been obfuscated because the locations are not publicly known; you have to be a member of the local caving association to have access to their caves database, and I don't want to publish locations I've learned from that database. But it is a fun crowd, so if you are interested in Swedish caves, do sign up! And the Finnish caving association can be reached here, do sign up there as well!

Coordinates: Prästgårdsfortet, Täby, N 59.482798 E 18.064322.




Car waiting for me:

The forest path:

Photos (c) 2017 by Jari Arkko. All rights reserved.

Wednesday, October 18, 2017

2nd Majvik Bunker

And now, with batteries in my flashlight... I stopped at another bunker in Majvik on the way home from the office.

This time it was obvious that one could enter, and I did. The bunker's main exit tunnel is still mostly intact as you look at it from inside, but ends abruptly, as if it was closed off on purpose. The upper small exit hole was what I used to get inside. A bit of loose, broken concrete pieces around, so treading carefully... interesting partially broken rooms, stalactites starting to form.

This place is next to a walkway, 100 meters from the Majvik facilities parking lot, very easy to find. Coordinates: N 60.16660530 E 24.54916611. And again, warning, the bunker is unstable and dangerous!

Outside view:

Ventilation duct:


Photos (c) 2017 by Jari Arkko. All rights reserved.

Tuesday, October 17, 2017

Majvik Bunker

It is getting dark very early in Finland, so today I stopped to see a possible bunker in Majvik on the way to the office. I found a bunker with clear entrances go inside, as well as a small roof cave on a cliff near the bunker.

The bunker turned out to be half under a sand road. Behind it was a beautiful rounded rock cliff, with a horizontal crack running across the cliff half-way up. In a couple of places a person could fit under the roof that forms, the bigger place probably a tight fit for three people or so.

Fortunately, the bunker seemed possible to enter, via blown up stairs leading to space between two concrete walls leaning against each other, or from a dirt tunnel leading under the bunker roof. Unfortunately, I had taken a flash light without good batteries. And I was in work clothes, so I decided to leave the entrance to another time, perhaps also going with someone.

Coordinates of the bunker: N 60.16195257 E 24.54408242.

Coordinates of the cave: N 60.161911 E 24.544294.

Again, the bunker location was found from the Lynx parenteesi page.

Bunker entrances:

The small cave:

Photos (c) 2017 by Jari Arkko. All rights reserved.

Monday, October 16, 2017

Bunker on the Tulikukka Alley

I used the "Parenteesi Suunnistuskartalle" database from Lynx and coming home from work, stopped at bunker location in Sarvvik.

Not much to be explored, really. A fenced 5x5m area, with concrete covering what holes they may have been earlier. Outside the fenced area, a rectangular depression leading to the fenced area. Most likely, this was the entrance tunnel which has been destroyed.

Just outside the fence, there was a wall still visible in the ground, and in the depression... there might be some opening to explore, although it is perhaps unlikely. Too much vegetation, not the right clothes for exploration, and being alone, I didn't want to push it.

The place is near the roundabout between Sarvvikintie and Sarvvikin Puistotie, and near Tulikukkakuja. Coordinates: N 60.15354417 E 24.60185852.

Photos (c) 2017 by Jari Arkko. All rights reserved.

Tired from a day of caving...

Ralf and I went to Torhola on Sunday to draw a map. We made some progress in that, but oh boy, there are so many problems, question marks, and on top of that, it is a lot of work in cold damp place!

It was fun to be in Torhola for an entire day though, with a steady stream of tourists coming to visit the cave. Oddly, most of them turned around at the cave entrance, no flash light, seems too difficult. And two odd guys with helmets and weird equipment! Even if we tried to say you can visit, gave them lamps, explained the cave, and gave some even a bit of tour. The small kids were the most interested in hearing about the cave and most daring to explore though.

The problems had to do with the fact that I had not calibrated my cave measurement device before, and trying to do it before this trip, I run into problems. Not sure if my technique is wrong somehow, or if the device has an issue. After calibration it claims decent accuracy, but the size of compass error is 10x what it should be. Maybe I made a mistake in assembling the device, forging a metal screw somewhere, or bent the mother board, or something?

It is also surprisingly difficult to use the modern smartphone-based software applications for caving. A big part of the problem is that I have no experience in using them, and without someone showing the proper technique by hand, the manuals are not really explaining how to do some of the things I wanted to do. For instance, it is difficult to correct information that the application determined based on measurements, such as what type of a measure a particular data point is. The flow in the applications is easiest when surveying long continues tunnels, but not at all intuitive when the cave branches in many directions all the time.

More about the map later.

Photo (c) 2017 by Jari Arkko, drawing by Ralf Strandell. All rights reserved.

Sunday, October 15, 2017

Killinmäki Bunker

There's just a little bit of warning tape, but most of it is gone. And one danger sign in a tree, visible from one direction only. The bunker is gone though, or hiding underground, with no easy way to enter. Just some holes in the ground that one needs to be careful of not stepping into.

We visited the bunker in Killinmäki based again on the parenteesi maps from Lynx, and the same Gillobackaträsk map that we used couple of days ago as well.

But this time there was not much to see, the bunker is destroyed, buried, and only these odd holes leading down to the ground remain to cause a danger for the occasional walker. The place is also near an area of houses, hopefully the kids do not play here.

The place is up the hill from the intersection of Vanha rantatie and Kvisintie in Jorvas, Kirkkonummi. Coordinates: N 60.131213 E 24.485167. Again, this is a dangerous place, do not visit if you do not know how to be safe.

Photos (c) 2017 by Jari Arkko. All rights reserved.

Degerby ZIF-25

Googling for more information about the Kirkkonummi bunkers, I found out more bunkers, obviously. But also a tidbit that there maybe 250-300 bunkers in the Kirkkonummi area.

On Saturday Janne and I visited a "touristy" bunker in Degerby, Inkoo. This bunker was of the type ZIF-25, with again one round door. The bunker is probably similar to the one we saw in Masala earlier. That is, one made to house a 100 mm gun. The bunker type is large, with two floors, several rooms, and usually at least two exit tunnels.

This particular bunker is very easy to reach, next to the road at Inkoon Rannikkotie 551, Degerby (N 60.078693 E 24.144999). There's an easy parking spot on the grass, the round gun door is the way to enter, and there's a wooden platform to stand on inside. On the right side there's even a light switch!

(Of course, we didn't stay on platform but explored a bit further in this totally blown up piece of concrete blocks and twisted rebar. On the safe part, half of the bunker seemed too dangerous to enter. Still, there's too much rebar even on the other side, be careful out there if you make a visit.)

The Degerby pages and the Porkkalan Parenteesi pages have a bit more information.

Photos (c) 2017 by Jari Arkko. All rights reserved.

Thursday, October 12, 2017

Jorvas Bunkers

How can one work somewhere for 25 years, and NEVER visit a lake just a few hundred meters away? I really don't know, but in my defence I went there today. And found trenches and flooded bunkers.

Kirkkonummi underground is the theme of the month, apparently.

Next to my office there's a lake, Gillobackaträsk. A forgotten lake, between a rarely visited cliff and the highway. Per the orienteering club's map of Russian occupation-time remains, there was supposed to be a trench, three dugouts, and two bunkers on the lake's southern shore.

We set out to find them with Jarmo. By the way, I'm so thankful that he joins many of my adventures, be they underground or on skis. Thank you! But for some reason none of my colleagues wanted to join the wonderful walk to the muddy forest in pouring rain, in the darkening evening. Very odd.

Anyhow, we found more possible dugouts than the map indicated (though we can't be sure if all have been made by Russians, or are really dugouts). We found the zig-zagging trench, now more like a ditch, and a very interesting bunker. Despite searching for half an hour on the right spot, we did not manage to find the other bunker though. Strange. Clearly we were on the right spot, because there were excess stones dumped nearby.

But the bunkers can be very hard to see, so was the bunker we actually did find. And once again, there was a hole in the bunker that one could attempt to enter. Or even walk into it by merely wondering in the forest, if one were not careful enough. 

The entrance had a few of the rebar steps still usable, so I climbed to the bottom. The bottom was filled with water, but I had tested that it wasn't too deep for my boots. At the bottom the rest of the bunker continued through a corridor. However, the water deepened immediately after the entrance, to maybe a meter and half deep, leaving only a few tens of centimetres of air on top. We would have needed wetsuits to continue, and would have had to wade in the water without knowing what ammunition or other dangers lay underneath.

So I came up, and we continued the tour. But this bunker was definitely interesting, and worth visiting. Glad I could snap a few pictures from the inside.


Update: Doh, per the video that Jarmo found later, we missed an entrance to the bunker. Obviously, bunkers will have at least two entrances! It also seems that the bunker can be dry at times. In October 2017 during our visit, southern Finland has received exceptional rainfall. 

Warning: be careful in visiting any of these structures. Bunkers can be particularly dangerous.

Pictures from the bunker:

Picture from dugout 1:

Picture from dugout 4:

Picture from the trench:

Other pictures:

Photos (c) 2017 by Jari Arkko and Jarmo Ruuth. All rights reserved. This blog article is also available on the TGR site