Sunday, May 22, 2022

Sutro Baths Tunnels

 

The Sutro Baths were luxurious swimming pools on the San Francisco seafront, in an almost all glass building, built in the 1890s. Complete with salt and freshwater pools, slides, and 30 swinging rings, and a springboard. It was served by two rail lines, one of these being the Sutro Railroad, another creation of Adolph Sutro, a famous engineer and industrialist and mayor of San Francisco! In the 1900s the facility fell into disrepair and it burned down in 1966. Today only ruins remain, including the pool basins, a settling pool, and tunnels. 

The tunnels are approximately at N 37.780777 W 122.514105. Note that there are multiple tunnels, the main walkable tunnel that is easy to spot, it goes through the cliff and opens up on the other side to rocky views of the sea. You can't continue, but can see the view. Inside the tunnel there are holes that lead to sea caves and cracks. I couldn't tell if these were there in the beginning, or if the rock has eroded since building the tunnels.

There's also a lower tunnel that is usually flooded. Apparently the lower tunnel was used to pump seawater during low tides to slowly replace the pool water; at high tide the water would naturally flow to the pools and replenish them within one hour. It doesn't seem to be easily accessible today, or at least one would have to be ready to use rubber bootss. 

While most of the ruins are at the seashore, if you walk to the observation area above the cliffs you will find more ruins, this is recommend for the views! From here you can also see (closed) stairs that lead down to an area above the lower tunnel. And from the observation area you can find further steps that lead to the Sutro Baths Trail and the Coastal Trail through the Golden Gate Recreation Area's beautiful park. Much recommended as well.

The entire area is dangerous, please be careful and do not fall from the cliffs or to the water. Don't go to closed areas.

More information about the Sutro Baths can be found here and here and here, in the Wikipedia article, or in the book "Sutro's Glass Palace - The Story of Sutro Baths" (Amazon link). More information about Adolph Sutro can be found in his Wikipedia article. Another creation of Sutro is by the way the Sutro Tunnel, a flood control tunnel in Nevada.

The Sutro Baths ruins, main area:

In their time, the baths looked like this (picture source is from Wikipedia, both pictures are postcards and in public domain, the first one is by W. C. Billington, the other one by unknown. What wonderful swimming places these have been!


The main tunnel (see also the opening photo above):



The lower tunnel:

Views from the observation area:

Coastal Trail views:

Other San Francisco views:

The author:

This article has also been published at TGR. Read more urban exploration stories from theurbanexplorer.net, and other underground stories from planetcaver.net. Read the full Planetskier series at planetskier.net, or all blog articles from Blogspot or TGR. Photos and text (c) 2022 by Jari Arkko. The historic photos are in the public domain, and from Wikipedia. The last photo is by Paul Wouters. All rights reserved.

Saturday, May 21, 2022

DFW!


I'm on my way back from a work trip in the US, and making a rare stop (for me) at DFW. Interesting place, and the airport seems to work well, changing from flight to another is easy, etc.

More flying and travel stories at planetflier.com. Read the full Planetskier series at planetskier.net, or all blog articles from Blogspot or TGR. All photos and text (c) 2022 by Jari Arkko.

Thursday, May 19, 2022

Moaning Caverns adventure tour

 

Moaning Caverns is a limestone-marble solutional cave in Vallecito, California. It is about 200 kilometers east of San Francisco, on the foothills of the Sierra Nevada mountain range. The main show cave attraction is the 165-feet high massive hole, but the cave extends further down in smaller passages under the big room, getting to a depth of 410 feet or 120 meters. An adventure tour explores some of these parts, which is why I was here. But there are other interesting aspects of the cave as well -- at the bottom of the main room there's a large pile of animal and human bones, presumably from whoever fell down to their fate here.

Bones covered by calcite deposits:

The main room has a staircase welded together from stairs of an old warship. Scary, but regularly inspected:

The cave is also interesting in that it has both limestone and marble parts. One of the tight squeezes on the adventure tour is actually between two beautiful slabs of white and blue marble, polished smooth by previous cavers. The slabs slope upwards and are spaced just barely far enough apart that a helmet fits in. Not much room:

 

Other squeezy parts of the adventure route include the Birth Canal, is a tight climb out of a hole right after managing to pull yourself out from between the marble slabs. There's also the "Meat Grinder", where you need to negotiate inconveniently placed rocks, like a puzzle where you have to fit your body just the right way to pass through. It turns out that this can involve painful grinding of the sensitive parts of cavers.

There's more, chimney climbs, rope-assisted descents and ascents, and smaller detours that require climbing skills.

What I found particularly interesting was a small room opening through a hole from the Lower Mud Flat. This room is decorated by helictites. These are small cave forms, like stalactites but which changed their direction of growth in different stages of their development, for reasons that are not fully understood even today. Direction changes might be due to capillary forces, wind, bacteria, or other reasons. 

Here's a picture of the helictites:

I ended up continuing my quest for 3D scans from caves. The entire cave is too big for my iPhone lidar sensors, which has only 4-5 meter range, when the big hall is 50 meters across. But I did scan two smaller rooms from the cave, the Lower Mud Flat and Helictite Rooms.

There's a nice rotate-on-your-screen version of these 3D models here and here. The corresponding 3D models can be downloaded in GLB format here and here, and in Blender format here and here.

Here's a snapshot of the Helictite Room model:


There's also a video of the models rotating around:


Nice cave forms:





But boy, do they have rules in the Moaning Caverns. Check this out:



And an advertisement for the expedition tour. $95, or with tax $115:


And here's me on site:


The Moaning Caverns website is here, and the wikipedia article here. If you decide to take on the adventure tour, ask for Tyler -- he's an expert guide and can take you to all places that you could possibly want to go to, and more :-)

This article has also been published at TGR. Read more urban exploration stories from theurbanexplorer.net, and other underground stories from planetcaver.net. Read the full Planetskier series at planetskier.net, or all blog articles from Blogspot or TGR. Photos, videos, and text (c) 2022 by Jari Arkko except where otherwise indicated. All rights reserved.


Tuesday, May 17, 2022

LAX how I have missed you!

 

Oh, I missed you so so much, LAX! It has been YEARS. But upon arrival, I tried to follow your signage to change to another terminal and ...



More flying and travel stories at planetflier.com. Read the full Planetskier series at planetskier.net, or all blog articles from Blogspot or TGR. All photos and text (c) 2022 by Jari Arkko.

Tuesday, April 26, 2022

It's alive! (and street legal)

It’s alive! (and street legal) The cheap fixes - only about 1.6k 🙂 worked. And a 10+ year idle rpm problem also disappeared after the engine control circuit board was re-soldered. Still a few smaller things to fix in a month but no need to go back to checkup until next year 🙂

Approved:


Only one warning light left anymore, not sure what's wrong with lights, or even if there's anything wrong with them... Anyway, the lambda sensor warning light is gone, after being on for years.

More car stories in the Planetskier blog series at Blogspot. Photos and text (c) 2022 by Jari Arkko. All rights reserved.

Helsingin Sanomat published 3D cave models!

 

The main newspaper in Finland, Helsingin Sanomat, published a story from visiting three caves in the Helsinki region with Harri-Pekka Pietikäinen, the author of a recent caving book.

It was a great article, and I'm very glad to see attention to the book! But it was also interesting that the newspaper journalists' decided to go even beyond the otherwise interesting article and include 3D cave models in the article. On the web version the user can navigate the models of the Torhola cave in Lohja, Grottberget cave in Siuntio, and the Högberget cave in Kirkkonummi. The models are my models, I was happy to provide the newspaper this material!

The article is available here (requires subscription, but free two-week trial subscriptions are available). The models are also stylized nicely and labeled with few key cave parts. Well done!

The original models are aren't labelled with cave parts, but are available in the Planetskier web page. They are also in a form that allows flying through the cave and rotating it on your browser screen:

Read more urban exploration stories from theurbanexplorer.net, and other underground stories from planetcaver.net. Read the full Planetskier series at planetskier.net, or all blog articles from Blogspot or TGR. Photos, videos, and text (c) 2022 by Jari Arkko except where otherwise indicated. All rights reserved.

Sunday, April 24, 2022

Baumannshöhle

Running into an unexpected cave during travels? Very nice. To a show cave that was opened in 1646? Even nicer! We were on our way to visit the ski hills in the Harz region in Germany when there was a sign for a show cave -- the Baumannshöhle. Upon returning from skiing, we were able to visit the cave as well, just before it closed.

Baumannshöhle is the oldest show cave in Germany, discovered in 1536, visited by many people over the centuries, including Goethe and others. Show cave tours started in 1646!!!


Show caves in Finland

This actually got me interested about show cave history. In 1646 there was barely anything in Finland. The first published mention of a cave in Finland was already in 1424 [1,2], but there isn't a proper show cave in the traditional sense even today. Unless one counts popular, well known caves such as Torhola or the Turku Luolavuori caves, or guided tour services to caves such as Koli's Repouuro [3]. Interestingly, Baumannshöhle was already mentioned in 1829 in Finnish newspapers [1]:


Show cave history in the world

But when did this show cave thing actually get started in the rest of the world? Per Wikipedia [4] the first show cave was established in 792 at the Reed Flute Cave in China, and the first one in Europe, Slovenia's Postojna Cave with its first tour in 1213. The article also mentions that the first "authorized" cave guide starting running tours in 1649 in Baumannshöhle.



Reed Flute cave: (Photo source: Dariusz Jemielniak - Own work (CC BY 3.0))



Postojna Cave: (Photo source: Donald Judge from England - 1.4.13 1 Postojna Cave 61 (CC BY 2.0))


Very interesting, but of course this is all a bit a question of definitions as well. Is it necessary to have some kind of permanent setup, trails etc., or does taking people on a commercial hike to see a cave also count? And what kind of a show cave was Baumannshöhle between 1646 and 1649, before the "authorized" cave guides? Unauthorized cave guides, or no guiding? But how is that different from a wild cave? Or is the determining factor whether you have to buy a ticket?

What about those features, trails, etc? Some data:

  • The first experiments with electric lights started in 1880 in Australia's Chifley Cave [4].
  • I was unable to find out when the first gated/locked caves appeared, but presumably very early on, since people did live in the caves. But did you know that there is a standard for cave gates? See reference [5].


Different kind of show cave: Let's not be cruel to small animals!

Also,  there's a very interesting case of a show cave in Grotte di Cane (Cave of Dogs) [1,6]. This is a small cave near Vesuvius, and subject to volcanic activity, with carbon dioxide leaking into it. Guides would take tourists and dogs to the cave, and the dogs would faint, being less tall than humans. The dogs would then be thrown out to Lake Agnano to be revived. Except that they did not always get revived, and there were complaints during 1800s about the cruelty... in the end the lake was drained, and the cruelty stopped.


Photo source: Anonymous, probablement Jules Marie Désandré - L'air et le monde aèrien, an 1865 textbook by Arthur Mangin, p.162



Photo source: Sieur de Rogissart - Les dĂ©lices de l’Italie, Vol. III, Leida, Pierre Vander, 1706

Modern measurements in the cave indicate 50+ degrees and 80% CO2 levels just nine meters from the entrance. Not recommended for a visit!


More about Baumannshöhle

But back to the Baumannshöhle: the best source for information about the cave is the German-version of the wikipedia article (link). The website for actually visiting the cave can be found from this link. And the coordinates for the cave are N 51.754790 E 10.843302.

The cave itself is about 2 kilometers long total, the showcave part being maybe few hundred meters. This is a karst cave, i.e., has stalactites, flowstone, etc. The most impressive feature of the cave is the biggest hall, named after Goethe: the Goethe hall & Wolfgang Lake. Concerts and events are held here regularly.

Photography on the cave tours is unfortunately forbidden. Fortunately I was able to find some photos from the Internet to show what the cave is like!





References

[1] Personal communication with Ralf Strandell, 2022.

[2] Suomen keskiaikakirjeiden kokoelma Diplomatarum Fennicum, DF 1743, 1424-03-02. NARC, 1424.

[3] Luolaseikkailu. Koli.fi.

[4] Show cave. Wikipedia.

[5] Cave gate. Wikipedia.

[6] Cave of Dogs. Wikipedia.


Acknowledgments

The author would like thank Ralf Strandell for interesting discussions about this case, and a lot of the information presented here is from him.

This article has also been published at TGR. Read more urban exploration stories from theurbanexplorer.net, and other underground stories from planetcaver.net. Read the full Planetskier series at planetskier.net, or all blog articles from Blogspot or TGR. Photos, videos, and text (c) 2022 by Jari Arkko except where otherwise indicated. All rights reserved.