Unikonlinnan pirunpesä (devil's nest at the poppy castle)

There are many caves called "Devil's Nest" in Finland. I guess a remnant of pagan beliefs of odd places or just a joke. This particular Devil's Nest is in Janakkala, and called the Poppy Castle. It is a bit unclear if there's human construction in some of the rock arrangements on this steep hill surrounded by cliffs, but the cave itself is definitely natural.

You'll have to get here by coordinates, there are no signs or even clear paths. The coordinates are N 60.85645 E 24.54095. A small road called Rehakantie goes just 100 meters away, and the highway isn't that far either, so if you're driving along the highway E12 north of Helsinki it is easy to stop. There's a couple of forestry roads starting from Rehakantie, parking on those is easy.

On the site there's indeed a steep hill. Worth visiting, but the cave itself is on the east side, and isn't easily accessible from the top. You would see the rectangular top entrance of the cave, however, not sure if it is possible to climb down or if there's a path to the lower cave from that entrance. But if you go on the east side of the hill you will spot some massive pieces of rock cracked away from the main cliff. The cave is on the south side of that.

I was in my business clothes, returning from a trip so I didn't crawl too far, but did squeeze in the cave's main hall. If I had climbed up a bit I could have continued in some further cracks, maybe also (doubtful) up to the top. I think I read somewhere that the cave would be 10 meters long. It is possible. A remarkable place nevertheless.

In addition to the narrow crack cave, there's a shelter/roof cave on the north side of the massive piece of rock.

More information can be found from the book of Finnish caves (Suomen Luolat) or in this Retkipaikka article.

According to google the "Poppy castle" is on the west side of the hill; it also has a cliff, but I did not have time to check that side out. There may be more interesting things on the other side, or perhaps the coordinates in Google are wrong. The coordinates I have above and where I visited is the same place that the Retkipaikka article talks about, though.

Photos of the cave:

The massive piece of rock on the side of the cave entrance (in the left/middle, in the inner corner):

Cave from the top:

The cliff:

Shelter/roof cave:

Photos from the hill:

This article has also been published at Planetcaver.net here. Read the full Planetskier series at planetskier.net, urban exploration stories from theurbanexplorer.net, and other underground stories from planetcaver.net, or all blog articles from Blogspot. Photos and text (c) 2026 by Jari Arkko. All rights reserved. 

Tampere: Conferences, hotels, saunas, and swims

Tampere. I was just here for a cottage visit ... but this time in a conference, staying at a hotel ... and visiting the hotel sauna and a local swimming pool for fun. Nice trip. Always love Tampere!

The hotel I was at was Scandic Tampere Asema, just by the station. Not even the only Scandic by the station, there are many :-) I chose this hotel because it was close enough for my conference and fit in the corporate price bucket ... but mostly because it was available. Busy times in Tampere in the spring, it seems.

View from the hotel room is at the top of this article.

There's a sauna at the hotel, just a sauna no pool. Actually, two saunas. But you have to book them when you arrive, and it is private use only, not entering at common times. Ok.

The saunas run on "always hot" stoves, ones that you have to open a lid to let the sauna room get heated. This happens almost immediately.

More sauna pictures:

Hotel itself and the routing table for the rooms (they badly need an addressing plan redesign):

The next day I visited Pyynikin uimahalli (the swimming hall of Pyynikki). It is practically in the city center. The pool is 25 meters, plus there's a kiddie pool, cold plunge pool and a tiny jacuzzi. But, the building is quite nice, you can see the city from the windows... not bad. On the main wall of the pool area there's a very nice mosaic artwork by Olavi Valavuori, of four naked characters. Nicely done.

The swimming hall is originally from 1956, and when built it was one of the first community swimming halls in the country.

Overall a very nice experience. Insides were also renovated in the 2010s, so the dressing rooms and other areas were quite good. Recommended. More information also in Wikipedia.

This article has also appeared here. Read all swimming stories at planetswimmer.com and sauna articles at saunablogger.cool. Or all blog articles from Blogspot. Photos and text (c) 2026 by Jari Arkko. Sauna and pool photos have been taken when the facility was empty or closed.

Early season cottage trip

Beach season opened at the cottage. Someone did swim but I will save the full immersive experience for later 🙂 March is earliest that we’ve been to the cottage, ever.

This article has also appeared here. Read all swimming stories at planetswimmer.com and sauna articles at saunablogger.cool. Or all blog articles from Blogspot. Photos and text (c) 2026 by Jari Arkko. Sauna and pool photos have been taken when the facility was empty or closed.

Hole in a mountain

Dongchong community and the Dapeng Peninsula are in the outskirts of Shenzhen, China. A beach resort, said to be Shenzhen's version of the Maldives. Clear, beautiful colored waters, tranquil beach, a village... and a hole through a mountain. The Chuanbi Rock, Piercing Nose Rock, or Elephant Trunk Gate cuts across the very end of the peninsula mountain. A see-through hole 18 meters high, 9 meters wide and 46 meters long.

So I arrived at the beach town, but it came immediately clear that getting to the cave wasn't necessarily obvious. The government websites had said that I could walk on the beach if the tide was low enough, but that I'd need to pay for access to the beach. The tide was mid-level, but eyeballing the path to the cave it looked like crossing on the beach was out of the question, waves were hitting the cliffs rising from the sea, and I couldn't cross them. 

And the beach itself was closed, the whole village seemed to be under renovation. All accesses blocked. I finally found an open gate to the beach and explored towards the cave, while knowing I couldn't get there by the beach. And then a guard with megaphone came shouting at me. We didn't share a common language but he pointed me to an upper route that I should take instead. I guess the beach was off limits in the off-season or perhaps the long row of tents on the beach was some kind of a military exercise.

I retreated and tried to go the house the guard had pointed me to, on the left side of the beach a bit higher up on the hill. When searching for the access to the beach I had already noticed that there was a road leading in this direction, so I took that road. Passed the house, maybe it was a hotel, but seemed quiet, and there were no signs for any kind of cave access payment booth, so I continued. After a while a gate and some barracks appeared, and another guard. Now I was a the right place, judging from all the signs.

I tried to ask how to get to the cave, can I buy a ticket. But the guard indicated it was closed until 5pm that day. And it was early 8 something in the morning. With the help of translation tools I explained my situation, deep craving for visiting cavers and having to get back to my meeting. He graciously opened the gate for me and guided me down the stairs. 

At the bottom of the stairs I had arrived on the beach, past the cliffs, and in front of the cave. There was a platform being constructed for viewing the cave, but the signs indicated that we shouldn't actually go in the cave. For once I complied with instructions, so took photos right in front of the massive opening, and then left.

The cave is roughly at coordinates N 22.491071 E 114.588586 (a bit uncertain, due to Chinese GPS coordinates and Google Maps misalignment/disturbances). More information about the cave here, here and here.

To get to Dongchong, I simply booked a "DIDI" taxi from Shenzhen city, which cost about 25 € one way. Then another one back. Easy, though there may be some public transport options too.

Cave:

Platform:

Beach:

See also my Hong Kong Dragon Claw Cave explorations the next day, as we were traveling back home via Hong Kong airport: link (alt. link).

This article has also been published at Planetcaver.net here. Read the full Planetskier series at planetskier.net, urban exploration stories from theurbanexplorer.net, and other underground stories from planetcaver.net, or all blog articles from Blogspot. Photos and text (c) 2026 by Jari Arkko. All rights reserved. 

Spring Wash

Finally, the car feels like new! A new, 34 year old that is. A bit rusty, but not dusty! Or muddy.

I've been waiting for this, but this month the car's been parked at the airport for 20 days as I was away, and before that the Finnish weather for was too cold to dare sprinkle water on the car, often -20 or so. The locks would have frozen, maybe doors too.

This article is also published here. More car stories in the Planetskier blog series at Blogspot or Planetskier.net. The photos and text (c) 2026 by Jari Arkko.

Dragon Claw Cave, Hong Kong

The Dragon Claw Cave, or 龍爪洞 as it is known in Chinese is a sea cave at the end of a small bay in the peninsula that extends between the South Bay Beach and Ching Hom Kok Beach, in Hong Kong. There's a nice but challenging path from the South Bay Beach to near cave, but as you near the cave the path turns into more difficult, at some point other hikers warned of a wild boar, then the path required an assisting rope, and then further down ... I didn't dare climb all the way down for the last 20 meters, for a fear of falling to the sea. But it is a beautiful cave even from this distance!

Afterwards I took a swim at the South Bay Beach before we headed back to the city. This was just a stop on our way with trains from Shenzhen to Hong Kong and then onwards to the airport; the easiest way to get to Shenzhen from Finland is to get the Finnair Helsinki-Hong Kong flight and use the trains or ferries to get over to Shenzhen. For the trains you'll need to switch at the West Kowloon station in Hong Kong from the border-crossing high speed train to the Airport Express train.

The area around South Bay Beach is very nice, there isn't much at the beach itself but on the way there there are high end apartments, a luxury neighborhood with more beaches, restaurants, etc.

Not much information about the cave can be found from the Internet, but here's one trip report to the cave. More information about the beach here. The beach is at N 22.224952 W 114.197536 and the cave at N 22.223054 E 114.195581.

Hike pictures:

The hiking paths go like this (courtesy of alltrails):

Cave pictures:

Beach pictures:

At the airport we were stunned by the size of it:

We had the fortune to be able to enter a lounge with the two of us having enough status for that plus guests. The Cathay Pacific Bridge Lounge was wonderful, with its two sides (Chinese style food on the left and international food on the right). What was very nice also how both food and shower access was given with alarm buzzers. Well organized.

Lounge photos:

Flight home:

This article has also been published at Planetcaver.net here. Read the full Planetskier series at planetskier.net, urban exploration stories from theurbanexplorer.net, and other underground stories from planetcaver.net, wimming stories at planetswimmer.com, sauna articles at saunablogger.cool. or all blog articles from Blogspot. Photos and text (c) 2026 by Jari Arkko and Lorenzo Corneo. All rights reserved.