5. GREEN KARST TRAIL

Bicycle Adventure into Slovenia's Karst

Join an unsupported unique multi-day cycling adventure in the beautiful Slovenian countryside. It was created by cyclists for cyclists.

Registration opens on Febriary 1.

18-22 June 2026

TWO PATHS THROUGH THE KARST

Choose your distance.
Choose your elevation.
Both routes reveal the same wild, beautiful and hidden world of Slovenia.

GREEN ROU​TE

The Green route is gravel paradise. 
Ride along macadam roads and cart tracks surrounded by forests (with asphalt only where necessary), past karst caves, intermittent lakes, and between remote castles and mansions.

300 km and 5,000 elev.

RED ROUTE

The Red route is an addition to the Green routeIt takes you through the native Karst, past white Lipizzaner horses, over white karst stone, red soil, and colorful vineyards, and up to the Nanos plateau.
 This route is more suitable for MTB bikes.

450 km and 7,500 elev

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START & FINISH

The start and finish are in the Postojna city centre (Slovenia) - ​only 1 km from the famous Postojna Cave.

  • Start: Thursday, 18 June 2026, between 9 and 10 am
  • Finish: No time limit; Bike Slovenia team welcomes finishers until Monday, 22 June 2026, 6 pm
WHAT RIDERS SAY ABOUT GKT
Polona O. / Beno N.

"​A very interesting route, the navigation is accurate, the suggested sleeping destinations are great, and the communication and support of Nataša and Tomaž... Top... Thank you 😉

We will definitely apply again for the next GKT because it is a once in a lifetime experience."

Žiga P.

"​​​​​What I remember most from GKT is the incredible diversity of the Slovenian Karst – from forests to windy hills and seasonal lakes. Unforgettable views and technically challenging climbs made this adventure truly special. Events like this remind us why we cycle – not for the destination, but for the journey.

Thanks to the organizers – and yes, this was not just a cycling tour, but a real experience."

Zlata L.

"​​GKT was my first multi-day gravel tour. 
The route itself was perfect for me – since I enjoy cycling alone, I really loved the forest and meadow trails that recharge your batteries.

Very precise navigation and enjoyable socializing with others at the end of the day. 

GKT is a perfect 10!"

Žiga J. / Andrej C.

Žiga: "​For top-notch gravel and an unforgettable bikepacking experience, you don’t have to go far.
Green Karst Trail is a one-of-a-kind event!

Andrej: "It’s an unforgettable experience of genuine hospitality and a true connection with pristine nature."

Both: "We highly recommend it."

Domen K.

"GKT is a unique adventure for all cycling enthusiasts who are not afraid of challenging terrain, through predominantly pristine landscapes.
The organization was excellent, and the GPX route recording is accurate with no navigation issues.
Accommodation along the route is not a problem.
Huge compliments to the organizers​ for selecting a truly fantastic route with breathtaking views in stunning nature.
See you again!"

Davor R.

"​Once again, thank you very much for the organization, the wonderful trip and the pictures and video sent.

Everything was very nicely done.
I'm happy to come to the next event and bring a few more friends with me.

All the best and greetings from Prekmurje."

 MORE ABOUT THE TRAIL

It is not a competition, but a multi-day challenge

For all lovers of endurance bikepacking, carefully planned and prepared by the BIKE SLOVENIA team.

  • unspoiled  Slovenian countryside
  • gravel paradise
  • local food & hospitality on Green Karst Friendly points
  • WhatsApp group
  • live tracking
 RIDE THROUGH THE HEART OF THE KARST

Predjama Castle

Planina plain

Lake Cerknica

Snežnik Castle

Škocjan Caves

Lipica

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 FOOD AND
ACC​OMMODATION

The choice of location and type of accommodation and/or food is up to each individual.

Along the route, participants will be offered free hot soup and drinking water at several Green Karst Trail Friendly Points. Some of these locations are also recommended as places for overnight stays, ​such as the "Beli Gaber" campsite.

Registered participants will be provided list of recommended accommodation providers (rooms, APP, hostel, campsite), ​including their location and route kilometer

  

  

  

GPX / WELCOME PACK

All registered participants who have paid the appropriate entry fee will receive GPX routes of GKT 2026 approximately one week before the official start, or no later than 13 June 2026.

All participants will also receive:
- coupons for freedrinks and/or food at GKT Friendly Points,
- a GKT 2026 tag to be attached to their bike and not to be taken off during the entire ride on GKT,
- a commemorative T-shirt with the GKT inscription,
- a cycling map of the region, where GKT will take place,
- a list of recommended accommodations along the route, and
- interesting gifts from the contributors to GKT 2026.

All participants also receive a tracking device, which they must return at the end.

  

  

  

FINISHER GKT​ 2026

Every participant who finishes the GKT 2026 in luntil 6 pm on Monday 22 June 2026 will receive a commemorative GKT 2026 finisher medal at the finish line and will be entered on the list of GKT 2026 finishers.

REGISTRATION AND​ PAYMENT

Each participant must fill in the registration form. After registration, the participant will receive an e-mail with payment instructions, as well as information and rules of the GKT 2026.

For more information and rules and entry fee click on:

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FAQ

Everything you ever wanted to know about GKT

Is the GKT a race?

No. The Green Karst Trail is not a race. It is an adventure, not a competition, created by cyclists for cyclists

Is the GKT supported?

The GKT is self-supported.

The Bike Slovenia team is at the start, the finish, and drives along the route, ready to help if you’re nearby. 

Tracking is provided for safety and all participants are invited to join a WhatsApp group for updates, communication and shared information during the event.

What is the route like?

The route runs through the countryside in the heart of the Slovenian Karst.

It follows mostly gravel tracks and dirt roads, with short sections on public asphalt roads only where necessary. Around 70–75% of the trail goes through forests, passing karst caves, intermittent lakes, remote castles and historic mansions.

What kind of bike do I need?

Green Route: gravel bike recommended

Red Route: mountain bike recommended

E-bikes: welcome

Can people follow me live?

Yes! Friends and family can follow your progress live on our website at www.bikeslovenia.si .

Each rider is equipped with a tracking device — not an app or phone — that you can simply put in your bag or attach to your bike. The device’s battery lasts the entire week, so you don’t need to worry about charging it.

Everyone can see your position along the route in real time.

What about accommodation, food and water?

The choice of location and type of accommodation and/or food is up to each individual.

Along the route, participants will be offered free hot soup and drinking water at several Green Karst Trail Friendly Points. Some of these locations are also recommended as places for overnight stays, such as the "Beli Gaber" campsite.

Registered participants will be provided list of recommended accommodation providers (rooms, APP, hostel, campsite), including their location and route kilometer.

What is included in the registration fee?


  • Official GKT 2026 GPX route
  • Tracking device (returned at the finish)
  • Coupons for free drinks and food at GKT Friendly Points
  • GKT bike tag
  • Commemorative GKT T-shirt
  • Regional cycling map
  • List of recommended accommodations along the route
  • Small gifts from GKT partners
  • And a few little surprises along the way — because no adventure is complete without them 😉
How many days does it take to complete?

The Green Karst Trail can be completed in 3–4 days on the Green Route, depending on your pace. The Red Route is longer and more challenging, usually taking 4–5 days to complete.

Riders are free to choose their own pace and daily distances — it’s an adventure, not a race!

What highlights are along the GKT?

The Green Karst Trail takes you through some of Slovenia’s most stunning landscapes and landmarks.

Highlights include:

Postojna Cave – the famous underground wonder

Predjama Castle – the largest cave castle in the world

Planina plain - he largest karst polje in Slovenia

Lake Cerknica – Slovenia’s largest intermittent lake

Snežnik castle - Renaissance castle nestled in the forest

Škocjan Caves - a UNESCO World Heritage underground wonder

Lipica -  home of the famous Lipizzaner horses

Nanos - Karst plateau with breathtaking view

Snežnik Forests – unspoiled natural wilderness


Scenic gravel roads and quiet forest tracks perfect for bikepacking

Along the way, you’ll experience the unique Karst terrain — white limestone, red soil, black pine forests — and plenty of hidden spots waiting to be discovered. Every day offers new vistas and a chance to connect with nature.

What can I expect at the finish line?

Finish the GKT 2026 by 6 pm on Monday, 22 June, to get your finisher medal, be added to the list of finishers and get a professional photo.

The Bike Slovenia team will welcome you with cold drinks — including at leastone free Slovenian craft beer — and maybe a few surprises waiting! Let’s toast to your achievement!

What is the route like?

LIVE TRACKING DURING THE GKT
THE NATRAL AND CULTURAL SITES ALONG THE TRAIL

POSTOJNA C​AVE

With more than 24 km, Postojna Cave is the largest tourist cave in Europe and one of the most attractive caves in the world. Take a ride on the legendary cave train and admire the magnificent work of nature through caverns, underground passages and grand halls. Meet the famous baby dragons of the world’s largest cave animal – Proteus Anguinus. 

PREDJAMA CASTLE

The mighty Predjama castle has been sitting in the middle of 123-metre high rock cliff, for more than 800 years. It even appears in the Guinness Book of Records as the largest cave castle in the world. It is also part of the legend of the outlaw knight Erasmus of Predjama who sucessfully resisted the siege of the castle for more than a year before being betrayed by one of his servants.

LAKE CERKNICA

Intermittent Lake Cerknica is a natural wonder, which constantly changes its appearance. Every year it appears on the karst plain between the Javornik Hills, the Bloke Plateau and Mount Slivnica. Its surface usually measures 20 km², but if there is a lot of water, it can cover an area of up to 26 km² and become the largest lake in Slovenia. 

SNEŽNIK CASTLE

The romantic castle is surrounded by chestnut, oak and lime tree avenues, walking paths and two little artificial lakes. Behind its current renaissance appearance, it hides a rich history, which goes back to the Middle Ages. 
A stroll through the castle’s four floors conjures up the atmosphere from 150 years ago.

SEASONAL LAKES OF PIVKA

Across the whole Pivka Valley, the valley at the foot of the Javornik Hills, there are as many as 17 picturesque intermittent lakes of varying sizes within an air distance of 15 km. Lake Palčje is the largest, as it is big enough to cover 300 football pitches when full. Lake Petelinje has the longest water retention time, of up to 9 months.

PREM CASTLE

Overlooking the picturesque valley of the River Reka stands one of the oldest castles in Slovenia - Prem Castle. With its impressive architecture and rich history, the castle bears witness to the strategic importance of this area from ancient times until the end of the 19th century.

FORESTS

The massif of Javornik – Snežnik encompasses the South-western part of Slovenia, comprising the northern part of the large Dinaric mountain range. It is a huge, 500 km2 stretch of uninterrupted area of forests and unspoiled nature. It is also one of the biggest serried and uninhabited woodland in the Central Europe, which extends into the Kočevje area and Gorski Kotar in Croatia.

LAKE BLOKE

Lake Bloke is of artificial origin, created by damming a stream around the year 1970. It is situated at an altitude of 748 m, the surface of the lake is 0.8 hectares, and the maximum depth is 3 m. There are extremely interesting wooden sculptures along the lake, which give the lake and its surroundings a homely feel.

MOUNT SLIVNICA

The highest peak of the hill which rises above the northern side of Intermittent Lake Cerknica is Velika Slivnica (Big Mount Slivnica). According to folk lore, this 1114-meter-high hill is home to witches, and from the top, it offers a magical view on Cerknica Plain, the lake, the Menišija plateau, the Javornik Hills and, in the distance, karst plateau Nanos.

BABNO POLJE
»the Slovenian Siberia«

Babno Polje is the coldest place in Slovenia, and is commonly referred to as »the Slovenian Siberia«. The absolute lowest temperature is believed to have been -39.6 °C (1929), although official records show an all-time low of -34.5 °C, which was measured in 1956.

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