Caves, geology and gentle walking: Croatia and Slovenia
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September 2026 – 8 days
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Explore Slovenia's breathtaking underground wonders on a gentle walking tour to discover the natural phenomena of this beautiful country. From vast underground rivers to awe-inspiring chambers filled with stalactites and stalagmites, these caves offer a unique window into the geological history of the region.
Slovenia’s remarkable karst landscapes are a treasure trove for geologists, biologists and anyone fascinated by the forces of nature. Take a deep delve into the intricate natural processes that have shaped these ancient caverns over millions of years.
Begin in Zagreb, Croatia's vibrant capital city, before travelling across into Slovenia, where you will explore the caves of Kostajnica, 沤upanova Jama, Bábji Zob, Postojna, Škocjan and Vilenica. You will also spend time discovering the beautiful Slovenian scenery through a series of gentle walks, exploring the cities of Zagreb and Ljubljana, as well as enjoying a relaxing day at Lake Bled.
You will be accompanied throughout by Rob Butler who is the professor of tectonics and department chair for geology and geophysics at the University of Aberdeen. As a passionate field geologist, Rob will enthrall you through a series of insightful talks relating to topics including structural geology. In addition to Rob, you will also be joined by an English-speaking tour leader who will offer insight into the culture and history of Croatia and Slovenia
This tour is designed for those with an interest in geology and nature lovers looking to explore the outdoors on a gentle walking tour. It provides insight into the science behind the stunning formations and ecosystems found in Slovenia’s world-renowned caves.
In partnership with Intrepid Travel.
DAY 1: ARRIVE IN ZAGREB AND MEET THE GROUP
Welcome to Croatia. Check in to your centrally located hotel. You will have the rest of the day to explore at your leisure.
Zagreb is located in the north-west of Croatia along the Sava river, sitting at the southern slopes of the mountain of Medvednica. The city has a long history, dating back to Roman times. Its medieval roots are reflected in its architecture and layout, particularly in the uptown and Kaptol areas.
In the evening, meet your fellow guests, tour leader and accompanying expert, who will give an introductory lecture on the trip ahead. The tour expert will give both evening lectures and walking commentary throughout the tour. Afterwards, you will head out to enjoy dinner together.
DAY 2: KOSTANJEVICA CAVE, KRKA CAVE AND THE MAYOR'S CAVE
This morning, you will travel from Zagreb and cross the border into Slovenia to the town of Kostanjevica, located in the south-east of the country. Here, you will visit Kostanjevica cave, a karst cave system that extends for around 2 kilometres. It was formed by the dissolution of limestone over millions of years and is known for its spectacular stalactites, stalagmites and other karst formations.
After exploring this natural wonder, continue to Krka cave, another remarkable subterranean site. Nestled in a tranquil setting, with only around 12 stairs, Krka cave features unique geological formations and provides further insight into the rich karst landscape of the region. Conclude the day’s explorations with a visit to Mayor’s cave, a lesser-known gem featuring stunning chambers and formations that highlight the region’s underground marvels. This cave is accessed via approximately 500 stairs.
In the early evening, you will arrive in Ljubljana, the capital of Slovenia, where you will check into your hotel.
DAY 3: LJUBLJANA CITY TOUR, INCLUDING THE CASTLE FUNICULAR
Today, you will enjoy a guided tour of Ljubljana, including a scenic ride on the castle funicular. Begin your journey at Prešeren Square. Stroll through the vibrant Central Market before heading to the funicular station for a breathtaking ascent to Ljubljana Castle. Once at the top, explore the the impressive courtyard, climb the viewing tower for panoramic views of the city and discover the rich history through the castle's exhibits. After the castle, return to the city to visit St. Nicholas Cathedral.
You will have the remainder of the afternoon at your leisure.
DAY 4: TRAVEL TO LAKE BLED AND VISIT BABLJI ZOB
Today, you will travel to Lake Bled, where you will begin with a guided tour to Bábji Zob cave. Perched at an altitude of about 1300 metres, it offers stunning panoramic views of the Julian Alps and Lake Bled. The cave itself is rich in stalactites and stalagmites, with intricate formations that have been shaped over thousands of years.
DAY 5: DAY AT LEISURE AT LAKE BLED
After a busy few days, we have included a day at leisure for you to relax in the beautiful surroundings of Lake Bled.
DAY 6: EXPLORE POSTOJNA CAVE SYSTEM
Depart Lake Bled and travel to Postojna, where you will explore the cave system found here. Begin your tour with a train ride that takes you deep into the cave system. This is a unique feature of Postojna cave, allowing you to cover a significant distance inside the cave quickly. Once inside, marvel at the stunning stalactites and stalagmites as you walk through various chambers, including the famous Great Hall, which is adorned with magnificent formations.
In the afternoon, visit Predjama Castle. This impressive structure is built into a cliffside and offers stunning views and fascinating history. Continue on to Oto膷ec, where you will stay for the night.
DAY 7: SKOCJAN CAVES AND VILENICA CAVES
This morning, you will visit the Škocjan caves which include the largest underground canyon in Europe, at around 140 metres deep. The caves are part of the Reka river system, which flows through the caves and contributes to the stunning underground landscapes.
In the afternoon, visit the Vilenica caves, located near the town of Lokev in the Karst region, close to the border with Italy. Some of the oldest known caves in Slovenia, they are renowned for their stunning geological formations, rich history and folklore.
Afterwards, return to Ljubljana, where you will enjoy a farewell dinner with the group.
DAY 8: DEPARTURE TRANSFER IN LJUBLJANA
After breakfast, you will be transferred back to the airport for your return flight. However, if you wish to spend some additional days in Ljubljana or other areas of Slovenia, you can extend your stay. Please speak to the team at Intrepid Travel, who can offer suggestions for you.
