Sunday, July 22, 2018

LivingWell at Heathrow Airport

The LivingWell gym club has a facility at the Terminal 4 Hilton in Heathrow. Is it any good?

No. This is a smelly, odd construction. Overpriced 20£ for access to the small, shallow pool and saunas. Water all over the floors in the changing rooms.

But, even a bad sauna visit is better than a good stay at an airport lounge for seven hours...

For some reason I had picked flights that allowed me to stay seven hours in London while changing planes. Except that when I got there, I couldn't figure any reason why I would have done so :-)

Pictures (c) 2018 by Jari Arkko. All photos taken after hours and while there were no other customers at the facility.

Wednesday, July 18, 2018

Caverne de Saint-Léonard

I had a free afternoon on an otherwise busy business trip in Montreal, and I wanted to visit Caverne de Saint-Léonard, a famous cave right under a city park. While this is a small cave, what I found was not your typical touristy show cave, but an adventure.

This was not a stroll on an asphalt path with handrails. We went on all fours, climbed ladders, and chimneyd cracks up.

The cave is just 50 meters long, but just last year, in October 2017, they discovered 350 meters more tunnels. On our climb, we got to see the entrance hole to the new parts, with a tempting ladder on the other side taking you down to the virgin cave. Sadly, that part cannot yet be visited. But it is interesting, a crack partially filled with water so it has to be navigated by an inflatable boat.

The opening to the new part:

The cave has been formed when immense pressure from kilometres of ice pressing on rock cracked the rock, a process known as glacial tectonics. In the years after the crack formed, water seeping to the cave has also formed stalactites, but this is not a karst cave.

We also saw some life in the cave, two small crawlers and one all-white (but dead) spider.

More information about the cave, booking of tours, etc can be found on the Quebec's Speleological Society's web page.

More pictures:

Tämä artikkeli löytyy myös suomeksi Relaasta. All caving related articles can be found at and all skiing related articles at

Photos and videos (c) 2018 by Jari Arkko. All rights reserved.

Monday, July 16, 2018

Canadian Heat Wave Snow

I had a great Sunday, starting with work work work, with some progress I think, then went skiing, and finally returned to have a nice sauna and a swim at the hotel. And afterwards met some fun new Argentinians from my meeting at a late reception.

And yes, I did find snow after a long heat wave here in Montreal. Maybe a six meters long stretch, perhaps even as much as seven :-)

Thanks to Patrick Corcoran and Greg Rich who kept me updated on the melt in Saint-Sauveur; thanks!

Photos and videos (c) 2018 by Jari Arkko. All rights reserved. This article has also been published at Teton Gravity Research.

Monday, July 9, 2018

Cave Radios with Bo Lenander

I had an opportunity to interview Bo Lenander, Swedish Speleological Society, about cave electronics and communications equipment. In this video he explains the equipment that he has built and what it can be used for. And then we try it out in the Gotland's Lummelunda cave!

Cave communications equipment and positioning tools have been in the news recently because of the Thailand rescue efforts. Caves are extremely difficult environment for communications, but there exists a few different types of equipment that can provide some form of communication.

These tools are used for both safety and rescue purposes, to inform those waiting above ground on the progress of an exploration party. The party can indicate whether they are proceeding according to plan, are delayed, or need help. And should there be an emergency, knowing the location of the cavers is obviously important.

The tools can also be used to pinpoint where an underground point is. For instance, in the Lummelunda cave, this location finding process has been used to improve the accuracy of the map of this 4-km long cave system. It has also been used to find the correct location to make a drill hole into the cave. (These holes can be used, for instance, to monitor the cave during winter months when a lot of water flows through it.)

Rock absorbs frequencies that we normally use for radio communication. This means that our phones, walkie-talkies and other equipment cannot be used. However, low frequency 1 to 100 Khz magnetic field can be used for communications. For instance 32Khz and 87Khz have been commonly used. Communication is typically possible through several hundred meters of rock.

Bo has built direction finding receivers since 1959, with varying capabilities for range, number of signals, and one- or two-way communication. Bo's paper at the 2017 International Caving Symposium is a description of his most recent equipment (link, paper starting from p. 321).

See also "Signal Seeker", short movie about Bo's dive exploration of the Bjurälven cave (at age 70!) and how they used the radios to locate points within the cave.

There are similar systems elsewhere in the world. British cavers have built many models, including the original "Molephones" and the later "Heyphones". Heyphones were named after their developer, John Hey. Several Heyphones were reportedly shipped to assist the Thailand cave rescue.

More advanced systems have been developed in recent years, and a number of commercial or semi-commercial systems have also appeared on the market. For instance, the Cave-Link system uses suitable radio communications as well as mesh networking among Cave-Link nodes to reach out to far-away distances in a cave.

If you want to know more about cave radios, I can recommend Dave Gibson's book "Cave Radiolocation". Shorter Internet resources include principles of cave radiolocation and the through-the-earth-mine-communications wikipedia article. A good list of all resources can be found from UK caving association's radio communications page.

In our test, here is caver Ralf Strandell with a probe that sends signal through rock:

Bo Lenander searching the cavers underground, using the red, gun-type listening device:

The yellow, square-format high-precision antenna:

Two in-cave probe models:

The entrance lake to the Lummelunda cave:

Lummelunda cave forms:

Above-the-ground tour in Lummelunda by Bo Lenander:

Ralf Strandell in the cave with the probe:

Photos and videos (c) 2018 by Jari Arkko and Jukka Erik Palm. All rights reserved.

Tämä artikkeli löytyy myös suomeksi Relaasta.

Other Planetcaver articles and videos are available at the website. See also the previous articles from Lummelunda, "A Kilometer Inside" (also in Finnish), "On the Beach" (also in Finnish), and "Lummelunda Cavers's Camp". Jukka's articles can be found from the Lumo, a magazine dedicated to nature photography. Finally, Jarmo Ruuth's video about the 2018 Lummelunda camp can be found on on YouTube.

Sunday, July 8, 2018


While at the caver's camp, I felt like I needed a shower... and a sauna. Solbergabadet in Visby to the rescue!

This nice community swimming hall is practically empty during the summer, but offers a 25-meter pool, jumping tower, and good saunas. The saunas are exactly the right temperature, which is a bit surprising for a community saunas and maybe also more generally many saunas in Sweden. But the sauna was decently hot but not too hot. Very nice!

I visited Solbergabadet a couple of times during the week, on almost all days. On one day though I had shower in the camp, using my shower bag that was hanging from a tree, warmed up water during the day. That was nice, too.

It was also fun to watch Ralf (who came with me one day) to swim backwards for cave diving practice. I need to try backwards swimming next time.

Photos (c) 2018 by Jari Arkko and All rights reserved. More sauna-related articles can be found at the website, and stories about swimming at the website.

Camping Sauna

At the Lummelunda campsite, someone had constructed a sauna out of tarp. Rocks would be heated in a nearby fire pit, and then brought inside for the heating of the sauna.

This sauna was not built by those of us in the caving camp, so we didn't get to use it. Would be interesting to try it out though!

Photos (c) 2018 by Jari Arkko. All rights reserved. More sauna-related articles can be found at the website, and stories about swimming at the website.

Saturday, July 7, 2018

Sikalammen luola. Cave of the Pigpond.

Evening exercise, drive to Nuuksio and visit Sikalammen Luola ("Cave of the Pigpond"). I found it, although the forest in the area is difficult going.

This cave is a small roof cave on a cliff, maybe 4-5 meters wide and 2-3 meters deep. Not really a proper cave, but ... this is what we have in Finland!

For some reason there is a brown children's sled in front of the cave.

The coordinates for the cave are N 60.27798 E 24.60321.

Photos (c) 2018 by Jari Arkko. All rights reserved. More caving articles can be found from

Cleaning up rat shit in the cabin

+10C, raining, high winds, cleaning up ratshit in the cabin, a fallen tree on our swimspot... HAPPY MIDSUMMER!!!

All we need now is a hail storm.

Seriously though, this is actually very nice, and the cabin brings many memories. Our sleeping spots in the other cabin are now ready, toilet is operational (although when wouldn't outhouses be?), and we are grilling in the grillhouse. With a bit more cleaning we may get to go to the sauna. And the nature is very beautiful. I feel good in this place.

Photos (c) 2018 by Jari Arkko. All rights reserved.

Friday, July 6, 2018

Lummelunda Caver's Camp

I spent the last five days on the beach in Gotland, camping with Swedish cavers in their yearly meet-up. A lot of fun, sunshine, grilling and old and new friends. And caving... more about that later. Heading home now.

(Above photo is by Jarmo Ruuth)

I have been to Lummelunda before. See my earlier articles "A Kilometre Inside" here (also in Finnish) and "On the Beach" here (again also in Finnish).

Photos (c) 2018 by Jari Arkko and Jarmo Ruuth. All rights reserved. Remember that pointers to all my stories about caving and skiing can be found at the ​ and ​ web sites.

Own sauna and bath whisk from the garden!

Rare vihta from own garden. I should cut down an overgrown jungle of trees, but first things first: using the branches for a good purpose :-) And the tree-cutting... maybe some day.

Photos (c) 2018 by Jari Arkko. All rights reserved.

Sunday, June 17, 2018

Utö Caving

This weekend I was at Tero's cottage in Särkisalo, and decided to check out local caves, if any. It turned out that there's quite a nice set of cracks, roofs, and boulders in Utö, at the Vårdgasberget.

The forestry road leading to Vårdgasberget is nowadays gated, so there's a 1.5 - 2km walk to get to the place. Fortunately the owner gave me a ride on the way there, as he was just passing as I was wondering what to do and whether I'd have time for the walk.

It is a wonderful area, probably one of the best views from a cave in Finland, with sea visible from the high cliffs of Vårdgasberget.

The caves can be approached either from the top or from below. From the top a small canyon with rocks covering it leads further down. There's a tight spot to enter the main cave, and it would be helpful to know that your feet will touch the ground if you go over the edge backwards (they do). From the main cave there are a couple of tunnels that lead further, but there are also a number of roof lids in front of the cliffs and the main cave, and there's also a large side cave to the left (when looking towards the cliff). Further to the right there's a large flat boulder at the top of the cliff, with a roof that one can be under of, and a possibly crawlable route to the other side of the boulder.

A nice area and well worth checking out.

Utö is nowadays reachable by car and bridge. The cave is at N 60.053758° E 22.854267°.

The cave begins at the top of the cliff:

The canyon entrance from the top:

Inside the main cave:

Sign in front of the main cave. The owner was worried about people starting fires in the cave, particularly now that the nature is very dry. Please don't make fires at caves, save them for official campsites!

View of the main cave and the roof in front of it from the bottom:



Me squeezing into the main cave:

Photos (c) 2018 by Jari Arkko. All rights reserved.