The Malaga man who has discovered the deepest aquatic cave in the whole of Spain

Malaga explorer and technical diver Antonio Moreno and his team have reached a milestone in underwater speleology: reaching a depth of 140 metres in an underwater cave at the Castril spring in neighbouring Granada province. This discovery stamps the exploration of the deepest aquatic cave in Spain, which has been possible without putting human lives at risk thanks to a robot designed to go where no on else dared.

- It all started with a speleologist group you founded, didn't it?

-The group was founded in 2000 by three-four friends who liked to go and explore caves. We decided to give it a more professional form and it now has 16 or 17 people.

- What is the name of the club?

-The Alhaurín el Grande speleology group, but we'd have to change that because it makes it seem like it's based there. I, for example, no longer live in Alhaurín, I'm in Coín at the moment, although I still enjoy going back there.

-Together with your team, you have discovered the deepest aquatic cave in Spain, in the Sierra de Castril. How did you get to that point?

-I am a sports technician in speleology, so you could say that I am the monitor. I have explored a lot and know quite a few sites, especially in the area of the Sierra de las Nieves, where you'll find the deepest cave in Andalucía, in Tolox, which goes down about 1,100 metres. Another thing is that I really enjoy both diving and technology, so we started testing these machines in areas that were easy to access and not too large in scale.

We started to look at some mines and flooded areas, where some cool things are still pending discovery. All this while continuing to test and invest in devices, which were getting better and better. We continued through the gallery, where we did many explorations, although they were somewhat impossible missions because they were very complicated and required technical equipment and a very specific and advanced level of diving.

-Where did you start?

-We went to the source of the Buitrera, which is commonly known as 'el Charco del Moro'. With the robot, we reached a depth of 87 metres and then stopped, because it was too deep.

-And that's when the idea of going to the Serranía de Castril came up?

-Yes, Castril is a very big spring, which I saw for the first time when I did my course as a monitor. They told me that nobody could go in there, but I'm talking about 15 or 20 years ago. The first people who went in there only told me that the spaces were very small, that there were collapsed areas, that very little was known about them... So I was very anxious to go there.

-That's when you started documenting?

Exactly. I saw on Facebook that the first person to enter reached 60 metres, but from that depth on, it's no longer normal air and you need to use 'trimix' (a helium-based gas mix). So these situations become much more complex and delicate because you have to carry many support tanks and people decide to stop exploring due to the risks involved.

- How complex is that cave?

-We are talking about very narrow spaces where you can hardly fit with diving equipment and you have to go through with a very small tank. The first 20 metres are very difficult. In fact, in the video I uploaded, you can see how the robot keeps bumping and that causes a lot of people to pull back.

-That's when you decided to use the device to see the depths?

- In the first video we made, we got to 100 metres, which is where the robot stopped, but we saw that the cave was still going deeper. So I decided to go back a second time, better prepare. However, the screen I use to control the robot warned me that I was exceeding its limit, though I still managed to reach 103 metres.

- And how far did you get?

-We have managed to reach up to 140 metres. The robot has a cable line that goes through very complex areas, with curves and bends, like a zigzag. We even saw a vertical 'fault' around 20 metres deep that the robot was able to navigate, which confirmed that the cave continues. And that's when we knew: we had broken the record. It is officially the deepest underwater cave explored in Spain.

-We are talking about a historic discovery?

-Yes, I already had an intuition. I knew that there were deep caves in Burgos, like Fuente Azul, where speleologists had reached 135 metres, but there the water starts to rise at that point and you can't go down any further. In Castril, on the other hand, the device managed to go beyond. All this without putting human lives at risk. It is a safe, technological and precise way of exploring the unexplored.

-Have you received a great response from institutions?

-Very little. We have received support from Castilla-La Mancha. But in Malaga, nothing. We have asked for subsidies and they only gave us 500 euros a year, and that's if you justified them very well. Now it's all private funds. Luckily, some manufacturing companies are seeing the potential in this.

- Well, it seems like an important milestone...

-It is. I think it's a national milestone and I'm surprised that Malaga is not taking advantage of it. Before, we used to get money for cutting-edge operations. But now the federation is more disconnected. The club is tired, and despite the impact of the discovery, it is difficult to mobilise support.

-However, it has had some effect?

-Yes, they call me from many places. I've been to Carmona, to Alcalá de Guadaira where there is a very unique old mill. All of that is of great interest. I'm also part of the Andalusian underground exploration group, which has agreements with town councils. They support us more there.

-Your case is quite unique - you don’t just discover, you also share your findings.

-I like the videos to be clear, didactic and to reach everyone. I don't want to do something just technical. The last one is 18 minutes long and shows the whole descent. It's doing really well on YouTube, although social media doesn't always help. That last video had already reached over 40,000 views in just a few weeks.

-And that's where the support comes from?

-Exactly. The sponsor looks at the visits, the impact and determines whether it's worth it. Thanks to that I was able to order a 2,500-euro battery. For them it's not much, but for us it's key. TikTok, Instagram... everything helps, but right now YouTube is what works best for us.

-What's next?

-To continue exploring. I'm applying for permits to fly drones, although it's difficult with so much bureaucracy. I want to film the Hernán Perea area - a very characteristic field in Cazorla. It is a spectacular place that has not yet been well documented. For me, all this is a way to leave a mark, spread the word and inspire others to continue exploring.