Exploring the Green Karst: The Križna Cave (Križna jama)

Slovenia’s Green Karst is abundant with caves, only a few of which are open to the public. Although the Postojna caves and the UNESCO-listed Škocjan caves are by far the most well-known and visited tourist caves in Slovenia, for a more authentic and less Disney-esque experience, I can recommend first-hand the naturally-preserved 8.273 metre-long Križna jama cave. The name, which translates as ‘Cross cave’, comes from the nearby church of St. Cross (Sv. Križa). It is the seventh longest cave system in Slovenia and offers a totally unique experience – a ride in a large rubber dinghy on one, or more, of its 22 underground crystal-clear emerald-green lakes.

I must admit I felt a little trepidation at the thought of entering the cave, togged up in the mandatory wellington boots, torch in hand. But I needn’t have! In fact, once inside it was quite the opposite.  The cave is so captivating that you can entirely forget about the outside world.


I opted for the short tour, which lasts around 1 hour and involves a 600 metre walk, followed by a short dinghy ride on the first lake. Here the lake splits and those taking the short tour return on foot the same way. The temperature inside the cave is a constant 8 degrees year-round, so be sure to wear your woolly socks and coats!

On entering the cave into the Great Hall, our guide, Gasper, first acquainted us with the entire cave system and showed us the part that we would be visiting.

We proceeded on foot, stopping at short intervals to see things such as ancient wall writings, the earliest among them date back to the 16th century,

The skulls and bones of cave bears, which are particularly notable for their size – the largest skull measures 56cm.

Gasper pointed out how the edges of the cave walls were rounded by the cave bears brushing past in the pitch black.

There is also an alternative tour to Bear Tunnel (Medvedji rov) for those particularly interested in finding out more about cave bears.

The Križna jama cave is known to contain around 45 animal species, making it the 4th in the world in terms of the number of species. During the tour that I joined, we came face-to-face with one, albeit it a sleeping one!

Then came the best bit. The dinghy awaits! I really didn’t know what to expect, but the overwhelming feeling as we sat in the boat with just the floodlights beneath the boat illuminating the crystal-clear water, was just total serenity and tranquility – a rarity in this modern fast-paced world.

There are also 2 longer tours available for real cave lovers. In order to protect the cave, visitor numbers on these longer tours are strictly limited. The 4-hour tour to the Calvary lake (Kalvarija) can be visited by only 1000 people per year (year-round, by prior arrangement), whilst only 100 people per year can take the 7-hour tour to the end of the 20th lake (from October to March, by prior arrangement).

Should you opt for either of the longer tours, you will be kitted out with all-in-one suits, and will need to take your own refreshments (a small snack, not an entire picnic!). After the first lake, you will transfer to a smaller dinghy and continue the tour partly on foot, partly by dinghy.

The 7-hour tour visits 20 lakes, culminating at Crystal Mountain, which is especially rich with stalactites.

One hour tours of the cave are available from 4.6 – 31.9 with no prior reservations required (at other times tours are available upon prior arrangement). Tours take place daily at 3pm on Saturdays, Sunday and public holidays from 4-30.6, thereafter at 11am, 1pm, 3pm and 5pm until 31st August, and at 11am, 1pm and 3pm during September. The one hour is suitable for all ages, providing you are able to walk on uneven ground. Prior booking for the longer tours is essential.

You can visit come rain or shine! So whilst in Slovenia, don’t miss the opportunity to see this amazing part of the mysterious Karst underworld.

More information about the Križna jama cave can be found here – http://krizna-jama.si/en/about-the-cave/ and more information about what else to see and do in the surrounding Green Karst can be found here – http://zelenikras.si/en/

Official cave photos: Peter Gedei, Gašper Modic.

© Adele in Slovenia



Mysterious Lake Cerknica – Now You See It, Now You Don’t!

Cerknica Lake is the largest intermittent lake in Slovenia and one of the largest in Europe.

For up to six months per year this fascinating, mysterious lake is, well, a lake, filled with water with a mean depth of over 6 metres. During the remainder of the year the water simply disappears, leaving just green, wild flower-covered fields.


The lake is fed by a number of openings with a series of subterranean reservoirs or caverns, some of which are above the lake level in the surrounding hills. In dryer months the lake completely drains into the reservoirs lying beneath it, revealing rich vegetation. In the wetter months, the surrounding higher reservoirs fill and discharge suddenly through subterranean passages into the lake, which very rapidly regains its volume and may even inundate the surrounding countryside.

A great way to visit, and to get a real impression of the vastness of the lake, is to cycle around the area. At the time of my visit in late June, there was still some water, in places up to 3 metres deep, though it was rapidly disappearing.


Every weekend bikes and canoes can be hired from the Notranjska Park Information Point, located in the main car park in the village of Dolenje Jezero. You can also, as I did, arrange a local guide for your cycling trip, who will take you to the best vantage points and provide plenty of local information.


We began by cycling through the valley of the Rakov Škocjan Landscape Park. This fascinating natural wonder, packed with karst phenomena, was formed by the Rak river, which springs from the Zelške cave, runs above the surface for 3.5kms, then once again goes underground in the Tkalca cave at the other end of the valley.


The main attractions are the two natural bridges at each end of the valley – Veliki naravni most (Big natural bridge) and Mali naravni most (Small natural bridge). There is a well-marked walking trail that leads between the bridges and to other parts of the valley and information boards are provided at the main points. On a hot summer’s day, it was a wonderful place to seek respite from the heat!


This place offers wild nature at its best, no crowds, just the chance to savour up close the fascinating geological formations, of which there are plenty.


You can view them from up above or from down below!


We then continued to one of the best vantage points of Cerknica Lake from where one can really get an idea of its size. The whole area that you can see behind me in the photo below, is, for around half the year, a lake. If you look closely you can just see the last remains of the water at the lake’s far end.


Although its fascinating to see the lake when it is actually a lake, even if there isn’t any, or isn’t much, water, it’s still worth a visit. Regardless of whether you visit when the lake is or isn’t, a great way to get a full impression of this mysterious lake is to visit the Museum of Lake Cerknica at Jezerski Hram in Dolenje Jezero.

Although it has areas with typical museum exhibits, this is no ordinary museum. It is the impressive model of the lake, hand-built by the museum’s owner Vekoslav Kebe, that is the standout feature. The model, the result of three year’s work, shows the topography of the area as well as demonstrating how, and where, the lake fills and empties.


After viewing the model and listening to accompanying commentary and sounds of nature, narrated by Vekoslav himself, visitors move upstairs to watch a multimedia presentation, which is available in a number of foreign languages. The museum also houses a collection of tools and other implements, used by local at various stages of the year when tilling the fields or fishing on the lake.

The museum is open Saturdays at 3pm, and at other times by prior arrangement.

Drevak boats were once the staple way of transporting supplies across the lake. This one seen below, at the Museum of Lake Cernika, again made by Vekoslav (a man of many talents!), gives visitors a real impression of the size of the boats and the work that goes into mastering the art of making these long, curved vessels. More information about the museum can be found here – http://jezerski-hram.si/en/


In the past even larger vessels, as can be seen below, sailed on the lake.


Author of photo: unknown, photo collection: Julka Hvala – www.stareslike.cerknica.org

Every weekend during summer, Notranjska Regional Park hosts themed Sundays at the lake, offering visitors the chance to take part in a range of activities such as horse-drawn carriage rides, fishing and boat trips, guided hikes and bike rides, and botanical and ornithological workshops. Find more information about Notranjska Regional Park here – http://www.notranjski-park.si/en


More information about all this, and all the other sights of interest in the surrounding areas, can also be found at the Green Karst website here – http://zelenikras.si/en/

© Adele in Slovenia

The Phenomenal Postojna Proteus Phenomena!

Whilst I generally tend not to write about those places in Slovenia that are already huge tourist attractions, preferring instead to write about some of the lesser-known parts of this wonderful country that I now call home, the current phenomena that is occurring in the Postojna Cave is hitting the headlines all over the world and really is a major news story, so I decided it was time to find out more and see it up close for myself.

So, what’s all the fuss about? Well, it’s this weird and wonderful creature – the proteus – also known as the olm or humanfish – which has laid eggs and the world has been waiting to see if these amazing ‘dragon baby’ embryos will hatch.

The olm in Postojna Cave_photo Iztok Medja for Postojnska jama - Kopija

Photo: Iztok Medja

Today, Wednesday 1st June 2016, is a momentous day as the first one hatched and made its debut appearance!


Photo: Postojna Cave

The news about this significant, once in a decade, event first broke at the end of January 2016 when a cave guide noticed the first egg attached to the wall of the aquarium. The female then laid over 50 more eggs until she stopped laying on 10th March.


Photo: Iztok Medja

And then the long wait began for the team of biologists at the Postojna Cave, who have been carefully monitoring movements and, like expectant parents, have been eagerly awaiting the happy day! As any expectant parents will know, it can sometimes seem like a long frustrating wait but, hopefully, the end results are worth the wait! Though one has now hatched, it’s still a waiting game for the remainder.

Biologists at their daily work

Photo: Postojna Cave

When talking with the cave’s management team and biologists, and hearing their tales of tears of joy, I could actually sense the expectancy, excitement, and pride in the job. Yes, the Postojna Cave is a huge tourist attraction but it is also a significant place for research and development of cave habitat and it is clear this is something not taken forgranted.

Cave biologists inspect the eggs daily and remove any that are decaying, which is not an easy task. A biologist has to dive into the large aquarium and inspect the eggs in a difficult-to-reach spot that is half a metre below the surface.

These tiny embryos are fighting against the odds to survive, as only a small percentage have a good chance of developing into adults and there is also the risk of genetic mutations.

Photo: Iztok Medja

Photo: Iztok Medja

The more the eggs develop, the higher the pressure for them to survive. Whilst the Postojna Cave has an excellent programme in place for looking after the proteus, this mysterious animal is still at the mercy of nature and its unpredictability. Preparations for the potential newborns will be very demanding and therefore Postojna Cave’s biologists paid a visit to a French lab, returning with numerous pieces of valuable advice.

 Visitors can’t actually see the eggs up-close, since light, noise, and any other elements which could result in harm to the eggs, is avoided at all costs. Therefore, a screen has been provided for visitors where they can watch live footage of the eggs moving and developing.

Photo: Iztok Medja

Photo: Iztok Medja

Take a look at this short mesmerising video showing the movement and progress of the embryos.

As I had already visited the Postojna Cave on 2 previous occasions, this time, instead of taking the tourist train into the caves, I first visited the Vivarium Proteus where you can see and learn about all the weird and wonderful creatures that live in the cave system, then toured the new EXPO Karst exhibition, which is full of interesting and interactive exhibits about the cave’s history and formation. Apparently, if I grew like a stalagmite, I would be 18,000 years old!


You can learn about the fascinating Karst world and meet some of its inhabitants!


Find plenty more information about the Postojna Cave here – http://www.postojnska-jama.eu/en/home/ and keep up-to-date with developments here in the fascinating Olm Diary, written by the biologists in charge of the eggs – http://www.postojnska-jama.eu/en/news/2016/olm-diary/

For those who haven’t yet visited the Postojna Cave, I highly recommend it, it’s like nothing you’ve ever experienced before, and everyone, regardless of whether young or old, loves a ride on the mini-train!

Photo: Iztok Medja

Photo: Iztok Medja

© Adele in Slovenia