TUNNEL ABSEILING PLUS tour the underground

The unusual part comes first: this is not simply a cave walk. You enter the unfinished San Giovanni World War II fortress, then use ropes to descend natural rock before exploring its concrete rooms. The Abseil Plus version adds a second interior descent, including a rougher cascading rock and an optional paired descent.

I like the careful way the tour builds confidence, with a technique briefing, flat-ground practice, and an instructor-backed first descent. I also like the mix of history, atmosphere, and adventure, especially the audio-visual presentation and the final glass of wine. The drawback is clear: at 14 to 16°C, in dark underground rooms with uneven rock, this may feel demanding if you dislike enclosed spaces, heights, or slippery footing.

Key points to know before booking

• 550-meter underground fortress: San Giovanni combines unfinished concrete construction with natural rock formations.
• Three possible abseils on Abseil Plus: The first descents are beginner-friendly, while the cascading rock requires more care.
• Small groups of up to eight: You receive direct guidance rather than being lost in a large crowd.
• No previous experience required: Certified instructors explain the equipment and stay with you through each descent.
• Bring grip: Hiking shoes or sturdy sports shoes with non-slip soles are mandatory.
• A cool, theatrical finish: Expect audio-visual effects, a darkness challenge for the brave, and wine at the end.

What you are really signing up for

For $88 per person, this is a 150-minute active visit to a former military structure. You are paying for more than a short rope descent. The price includes entrance to the underground fortress, a guided tour, certified equipment, insurance, professional instructors, audio-visual effects, and wine tasting.

I see the value in the combination. A standard historic site visit gives you architecture and context. This one adds a physical challenge and a stronger sense of the building’s height, darkness, and rough surfaces. The small group limit of eight also matters. With a technical activity, waiting while an instructor handles several people is part of the experience, but a smaller group keeps the explanations personal.

Still, this is not a bargain activity for someone who only wants to see the fortress. If you have no interest in abseiling, choose the separate underground tour without that element. The Plus option makes sense when you want the history and the rope work together.

San Giovanni fortress: concrete, rock, and unfinished wartime plans

The fortress is about 550 meters long and was left unfinished. That incomplete state is part of its appeal. You see human-made concrete spaces alongside natural rock, rather than a polished attraction designed from the start for sightseeing.

The building remained forgotten and hidden until it was prepared for visitors. That gives the walk a rawer feel than a restored museum. You should expect an underground facility shaped by practical military construction, natural surfaces, and limited light. It is a place to observe slowly, not a bright, tidy exhibit with signs at every turn.

The fort was built on two levels, which gives the route a vertical quality even before the ropes come out. The Abseil Plus version uses that structure to add another descent. The history is not treated as a separate lecture, either. Your guide explains the site while moving you through it, so the building itself supplies the setting.

The first 30 minutes: learning the rope work

Both versions begin with an introduction to abseiling and the equipment. You do not simply arrive, clip in, and hope for the best. The instructors explain the basic technique, help you get familiar with the harness and rope system, and demonstrate a descent.

Next comes practice on a horizontal surface. This is a useful step for first-timers because it lets you concentrate on hand position and body movement without immediately dealing with a vertical drop. I would pay close attention here, even if you have used climbing equipment before. The goal is not to prove anything. It is to build a steady routine before you leave the flat ground.

The instructors are licensed and the equipment is certified to current standards and checked regularly. That does not remove every risk, but it gives the activity a proper safety structure. You remain responsible for following instructions and deciding which descent fits your comfort level.

A practical point is that you can choose on the spot which descent you want to attempt. The tour offers options based on difficulty, and the instructors provide support and backup. This is helpful for mixed groups, since one person may want the full challenge while another prefers the simplest route.

The first rock descent: a manageable start

The first vertical descent takes you down natural rock and toward the high underground rooms. The easier version involves walking down a vertical rock face while supported by the rope. For a beginner, this is a sensible introduction because you can focus on controlled movement rather than making a jump.

A second version adds a vertical jump. Both are described as suitable for beginners without previous experience, but suitable for beginners does not mean effortless. Heights, harnesses, dark surroundings, and unfamiliar movements can still make the moment feel serious.

Your instructors remain available for guidance and backup. The best approach is to go slowly, listen closely, and let the equipment do its job. You do not need to rush because the group is small and the activity is designed to teach the method as you go.

This first descent is included in both the standard Abseil tour and Abseil Plus. If your main aim is to try abseiling once while also seeing the fort, the regular version may be enough. If you want a fuller physical challenge, the Plus option continues to another descent inside.

Abseil Plus: the slippery cascade

The Plus version includes another abseil on a cascading rock inside the fortress. This section is more demanding because the rock is uneven and slippery. Non-slip footwear is not a minor suggestion here. It is mandatory, and the agency can refuse participation if your footwear is inadequate.

You prepare for this section by completing the earlier descents with instructor support. That progression is one of the strongest features of the format. Instead of beginning with the hardest surface, you first learn the movement, gain a sense of the harness, and then decide how far you want to go.

You may also try a simultaneous paired descent. That adds a social element, but it does not turn the activity into a race. If you choose it, follow the instructors’ timing and positioning instructions carefully.

I would choose Abseil Plus only if you are comfortable with the standard descent and willing to deal with wet or slick rock. The extra section gives you more for your money, but it also asks more from your balance and nerves. The regular Abseil version is the better match if you want a gentler introduction.

Walking through the two-level underground rooms

After the initial descent, you walk into the large concrete rooms of the fortress. The transition from natural rock to military construction is the visual idea that holds the visit together. You are not seeing two unrelated attractions. The route shows how the unfinished fortress and the surrounding rock meet.

Special effects accompany the walk. These include audio-visual elements and a projection that helps bring the site’s past into the present. I would not expect a full museum presentation or a long formal history lesson. The value is more atmospheric: the sound, images, darkness, and concrete rooms make the site easier to picture as a working wartime structure.

The underground temperature stays around 14 to 16°C. That will feel cool, especially if you are dressed for a warm Croatian day. Bring a warmer layer that allows movement. A bulky coat could get in the way of the harness, so practical sports clothing is the better choice.

You should also expect uneven ground during the walk. Hiking shoes or sturdy sports shoes with non-slip soles are the right choice. Open shoes, smooth-soled trainers, or fashion footwear are poor matches for this activity.

The final darkness challenge and return

Near the end, the tour offers an optional challenge for the bravest participants: switching off the head torches and finding the way out in complete darkness. This is a short but memorable way to understand how dependent you have become on artificial light underground.

You do not have to treat this as a test of courage. If darkness or enclosed spaces makes you uncomfortable, skip it. The tour already includes enough physical and atmospheric elements without adding a challenge that will spoil your afternoon.

At the exit, an air-conditioned van returns you to the starting point. The experience ends socially, with conversation and a glass of wine. That finish helps the outing shift from technical activity back to a relaxed travel experience. Wine is included, but do not drink before the tour. The agency can adjust or refuse participation if someone is under the influence of alcohol or drugs.

Guides, group size, and the level of support

The tour is conducted in English and limited to eight participants. That is a good size for a rope activity. You can hear instructions, ask questions, and receive help without standing in a large queue.

Sara and Marko have led departures with clear explanations and patient support. Their role covers both sides of the experience: basic abseiling technique and the story of the fortress. That combination matters because a technically competent instructor is not always a strong site guide, and the reverse can also be true.

The instructors provide professional guidance and backup, but you still need to speak up if you feel unsure. The tour lets you choose your descent based on your comfort level, so there is no good reason to force yourself into the hardest option. The smartest participant is the one who knows when the easier version is the right one.

Private tours and other dates or times can be arranged by request. That may be useful if you are traveling with a family group, a set of friends, or a schedule that does not match the regular departures. Confirm the meeting details directly before booking, since the supplied information identifies Zagreb County but does not give a precise pickup address.

Who will enjoy this, and who should skip it

I would recommend this to you if you want a historic site visit with a real physical element. It suits adults and children aged 10 or older who can follow instructions, tolerate cool underground rooms, and feel reasonably comfortable with heights.

It is also a good choice for a mixed-interest group. One person can come for the wartime fortress and another for the ropes, while both share the same walk, projections, and wine at the end. The small group format makes it easier to adjust the level of challenge.

I would not book it for anyone with claustrophobia or epilepsy. It is also not suitable for children under 10. If heights make you freeze, the underground tour without abseiling is the safer option to consider.

The activity is operated at your own risk, as is the entrance to the underground facility. Bad weather can lead the agency to change or adjust the tour. Inadequate footwear can also end your participation before it starts, so treat the shoe requirement as a firm rule.

My practical verdict on the $88 price

The $88 cost is fair if you plan to take part in Abseil Plus and value a small group, certified equipment, instruction, and a guided visit to a site you could not experience in the same way on your own. You are getting a full 150-minute program rather than a quick photo stop.

The value is less convincing if you are nervous about abseiling and expect to skip most of the rope sections. In that case, the non-abseiling underground option should be your first comparison. The regular Abseil tour may also be the better middle ground if the cascade sounds like more work than fun.

Free cancellation up to 24 hours before the start and reserve-now, pay-later booking provide useful flexibility. I would still check the forecast and contact the operator through WhatsApp at +385 98 316 322 if you need a private departure or have questions about the exact meeting point.

Should you book Tunnel Abseiling Plus?

Book it if you want your history outing to involve your hands, feet, and nerves, not just your camera. The best parts are the gradual instruction, the unusual unfinished fortress, the contrast between natural rock and concrete, and the chance to choose your own difficulty.

Choose the regular Abseil tour if you want a first rope experience without the slippery cascade. Skip both versions if you have claustrophobia, epilepsy, poor footwear, or no interest in heights. For the right participant, Abseil Plus offers a memorable way to see San Giovanni, with enough guidance to make a first attempt feel achievable and enough challenge to keep experienced participants interested.

FAQ

Where does the Tunnel Abseiling Plus tour take place?

The experience takes place in Zagreb County, Croatia, at the underground San Giovanni fortress.

How long does the tour last?

The tour lasts 150 minutes.

What is included in the price?

The price includes certified abseiling equipment, a guided visit and entrance to San Giovanni fortress, professional certified guides, insurance, audio-visual effects and projection, and wine tasting.

Do I need previous abseiling experience?

No. Previous experience is not required. The instructors explain the technique, help you become familiar with the equipment, provide a horizontal practice session, and demonstrate the descent.

What is the difference between Abseil and Abseil Plus?

The regular Abseil tour includes the fortress visit and one or two beginner-friendly descent options. Abseil Plus adds another descent on a more uneven and slippery cascading rock inside the fortress, plus the option to try a simultaneous paired descent.

What should I wear and bring?

Bring warmer clothing because the underground temperature is about 14 to 16°C. You must wear hiking shoes or sturdy sports shoes with non-slip soles.

Is the tour suitable for children?

Children under 10 are not permitted. The supplied information does not give a maximum age, but every participant must be able to follow the instructors’ safety guidance and manage the physical activity.

Can I cancel or change my booking?

You can cancel up to 24 hours in advance for a full refund. Private tours and other dates or times may be available by request through WhatsApp at +385 98 316 322.