Gaura cu Muscă cave in Romania

I had two choices for visiting a cave. One was reportedly larger, but also came with a river crossing on foot, hiking through bushes known to have venomous snakes, and a 10-meter vertical cliff climb without protection. I chose the other one, Gaura cu Muscă, or the "Cave of the Flies". This cave was supposed have an easy path to follow from the road. Yet, that easy path turned out to be not so obvious, so after hiking 50 meters up and gotten to an increasingly unstable and sketchy mountainside path, I gave up. But on the way back I realized there were alternate paths, and one of them lead to the actual cave. The views from inside this cave's oval-shaped entrance holes, over the Danube were nothing short of stunning!

Gaura cu Muscă is in Romania, on the cliffs facing the Danube river towards Serbia's Golubac fortress. The cave is slightly south of Romania's town of Coronini and the modernized St. Laszlo Fortress, all along Romania's highway 57 and in the Iron Gates Natural Park. There's a widening in front of the cave on the highway, so stopping and parking is easy. There's even an information sign for the cave. Nice!

The cave is openly accessible, but should be left undisturbed during the sensitive times for the long-winged bats (Minopterus schreibersii), long-fingered bats (Myotis capaccinii) and Mediterranean horseshoe bats (Rhinolophus euryale) populations housed in the area. As a result the cave should not be visited during the winter hibernation, December-March, or summer breeding seasons, June-July.

I found the cave with a simple Google maps search. There's actually two caves, the lower one that is most frequented by visitors and just 10 meters from the parking place. I call it the Gaura cu Muscă mai jos, "mai jos" for the lower one. The coordinates are N 44.664659 E 21.6990705. This cave is a very nice, green, a water-dripping moss cave. But it is just a couple of meters of actual cave plus some overhang, by my measurements 8.6 meters long.

The main cave is maybe 15 meters higher up and while I didn't fully explore it, it is beyond 100 meters long. I didn't explore it fully, because it was water filled, I was alone, and there were signs warning about deep water. Deep water by itself may not be an issue, but the main concern I had was the at-times muddy bottom where I might get stuck. But I think I covered most of the cave, except for the one last tunnel, but who knows :-) 

Here's what the water-filled cave looks like. While the water level is, well, level, the bottom isn't, there were shallower and deeper parts.

I call the main, upper cave Gaura cu Muscă de sus, "de sus" for the upper or superior one. The coordinates are N 44.664658 E 21.699194.

The cave is well known for its stunning views out of its entrances and over the Danube, like in the opening shot and here:

I scanned both caves using my iPhone's lidar sensor, and then processed the resulting 3D models to a plan view map, like here for the main cave:

A high resolution PDF version of the map with vertical cross sections can be found here. You can also download the 3D model here, or rotate it on your browser screen here. A picture of the model looks like this on a Blender 3D editing software screen:

For the lower cave, a high resolution PDF version of the map with vertical cross sections can be found here. You can also download the 3D model here, or rotate it on your browser screen here. Here's what the map and the model look like:

Lower cave pictures:

Upper cave pictures:

Path to the upper cave starts from the parking lot like this:

Here's a view from the wrong path towards the river. Very nice, but I don't recommend, it is too steep, the rocks are beginning to be unstable under your feet.

Pictures from the Golubac fortress on the other side of the river are shown below. More information from this fortress can also be found from its home page here.

A picture of the St. Laszlo Fortress:

The processing of the 3D models was tricky this time. I use the Polycam app on the iPhone, process them on the phone to a 3D model in GLB format, upload to the my own backend systems, use Blender to adjust where needed, and then use my own software, Cave Outliner, to turn the model also to a plane view and vertical cross-section maps.

But the Polycam app sometimes fails to work, particularly with larger models, and I did the upper cave in just two parts, being lazy and wanting to avoid error-prone manual joining in post processing. But now I found out that the process-in-cloud option in Polycam works somewhat better. You need to publish the raw data to their cloud, and then the processing takes few tens of minutes, and you can then rotate, download, etc. the resulting model as you please.

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, TGR. Photos and text (c) 2025 by Jari Arkko. All rights reserved. 

Green Cave

(Photo by dronepicr/wikimedia, CC BY 2.0)

A hole in the sky. Or in the roof, rather. This is what has given this cave its name, Zelena Špilja or in English the Green Cave. At noon, sun will shine through this small hole down to the water in the sea cave, and combined with the sea weed at the bottom of the water, a green light is created. I'm here though in the evening, but the cave is still spectacular!

There was actually three holes, the main one, a smaller one, and a tiny crack that also gave some light. The main one was beautiful, you could see the thin rock cover covered by green vegetation above, all shining in sunlight. Very pretty. But I had to wonder about the cave's future, given that the roof looked like being only few tens of centimeters thick. Some day the environmental erosion will cause pieces of the roof to come down, making the hole larger.

We got here with a speedboat tour, though, and no motor boats are allowed in the cave. This meant that I had to swim from the boat to the cave, and then inside the cave... not much, maybe 100 meters from the boat. And the cave is over 30 meters deep. In recent years I've been very nervous about swimming far from shores or the lake, given my heart problems. I guess I made an exception to see the cave :-) There was a little floating platform in the cave though, with handrails to hold on to. That gave some comfort.

The cave is on the island of Ravnik, off the shores of the bigger island, Vis. Vis in turn is a 2-3 boat ride away from the town of Split on the coast.

The cave is in these coordinates N 43.015605 E 16.224207. More reading about the Green Cave here: Wikipedia, YouTube promotional video, Nautica, Zen Travel Croatia, Diving Vis, and Explore Adriatic. We joined the Milaneze Marine tour (or one half of the tour). They are based in Komiža, and a full tour covering the day and multiple beaches in addition costs around 60€ per person. A half tour, just getting to the green cave and then back to Komiža costs around 30€. But the smaller boats from Milna near Ravnik may be an easier and more cost-effective option if you just want to see the cave, and are already in Milna or have a car to get there easily.

More photos from the cave:

(Photo by Dejan Sekuloski/Wikimedia, CC BY 3.0)

(Photo by Piotr Stós, Nautica, published here)

Here's the tour boat and some rocky shorelines of Ravnik:

The tour makes you visit the Milna, Zaglav, and Budikovac beaches, even for the half tour. We also swam at Zaglav, sadly Budikovac was closed se it could only be seen, but not actually visited on. The three beaches are shown in the following pictures:

There are by the several caves on the southern shorelines of the island Vis. We visited one of them with the boat, at the approximate coordinates N 43.009955 E 16.120934, on the rocky shores near the Podhumlje village. This cave is big enough for a boat to enter, but you can't go particularly far inside. Some smaller cracks of the cave may continue further. A few pictures:

There are several others, e.g., around the Srebrna beach (see another article). And one in these approximate coordinates, also near the Podhumlje village: N 43.007470 E 16.1091617. Picture:

My previous articles about caving and underground structures on Vis include: Tito's cave, Blue Grotto on the nearby island of Biševo, Srebrna Beach caves, Dog Beach mini-caves (2nd article), underground submarine base, Mali Hum tunnels, Vis missile bases, and Zagrebenje bunkers.

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, TGR. For more sauna and swimming stories, check out planetswimmer.com and saunablogger.cool websites. Photos and text (c) 2025 by Jari Arkko, except where otherwise indicated. All rights reserved. 

Swimming prohibition

I've been in a medical procedure, as a time slot opened in my hospital for an operation that I've been waiting for. This lead me interrupting a vacation and flying back to Finland, some great care in the Meilahti hospital, some sick leave, and hopefully getting improved health as a result. But it also led to a temporary prohibition for swimming and saunas, and heavy exercise. Fortunately I can still soak my feet in the pleasant waters of the Bodom lake, in Oittaa.

I've been here before, of course; this is near my home. One article about an earlier visit is here. And the official home page is here, and Tony Hagerlund's blog article is here.

This time they were setting the beach up for some supping and kayaking competition, and while there were almost no swimmers (it was a work day), there was a ton of activity for setting up spectator seats, power lines, judging facilities, etc. Just the TV crews alone were at least four big trucks.

For more sauna and swimming stories, check out planetswimmer.com and saunablogger.cool websites! And of course the Planetcaver, and Planetskier blogs for other stories in Blogspot and TGR! The photos and text (c) 2025 by Jari Arkko. All rights reserved. No photos of beachgoers were taken.

Ski, swim, and fly in one day: Myyrmäki, Pornainen and Helsinki-Vantaa

An active day, for sure. I needed to fly out today, but before that I wanted to get my August ski turns in the massive snow mountains of Myyrmäki's ice skating hall (picture above), visit my mom, and do a quick swim at a swimming place near her in Pornainen's Hietasen uimaranta (Hietasen's beach) in Vähä-Laukkokoski. A nice package for the day! The skating hall was open and there was a pile of snow, saw my mom, visited the beach with warm water and sunshine and no one else around, and had a pleasant flying experience in the air and at the airports.

My mom is staying at a care home, located on the “Happiness journey street”. She is doing very well and is indeed happy there 💚

These steps from the beach say "summer!":

Skiing was ... skiing, so always great 😏 What was important for me was to make a few turns, I managed two per run I think on most runs, and did ten or so climbs to the top of the "mountain". 

And at the airport I went to Finnair's Platinum lounge (on the Schengen side). I was surprised to see the sign below, do we really need say when alcohol serving begins? And doesn't the lounge open anyway at 5:30 am, so they always serve it? Or if they open it already at 5:00 am, maybe those passengers are already so zoned out that alcohol wouldn't even cross their minds...

More skiing photos:

More swimming photos below. Hietasen's beach has also been discussed in Tony Hagerlund's blog article here.

Flying photos, at the Helsinki-Vantaa airport:

Then on flight I got a nice meal (upgraded through some vouchers I have left, so I was in business class):

And in Split, Croatia, where I was headed to for vacation:

Read the full Planetskier series at planetskier.net, or all blog articles from Blogspot, TGR. For more sauna and swimming stories, check out planetswimmer.com and saunablogger.cool websites. For more flying stories, check out the planetflier.com website. Photos and text (c) 2025 by Jari Arkko.