Hidden beneath the waves in this small coastal town lies a forgotten undersea tunnel. It was build in the 70s, a time when Yugoslavia was rapidly developing its industry, which had an absolute priority. All resources were relentlessly exploited for industrialization regardless of cost. This town was no exception, so because it already had a bulk carrier unload facility present, it was chosen as the location of a new coke production plant. As the new factory location was right opposite the existing ship unloading facility, a 400 m long undersea tunnel was constructed connecting the two. Using a long conveyor belt, coal was unloaded from the big transport ships and transferred to the coke factory. But why didn't they build a bridge or gone around the bay, you might ask? The answer is simple, aesthetics. A bridge would interfere with shipping and take away from the bay's beautiful landscape.







The tunnel consists of individual pipes 40 m in length that were made on land and then loaded on a transport ship before being submerged and connected underwater. To not obstruct normal shipping operations, the tunnel was laid on pillows 6 m under the surface.







The cookery, with it's 250 m tall chimney began production in 1978. But after 16 years, and more than 13 million tons of produced coke, the plant was shut down due to high pollution and the tunnel left forgotten. Locals complained that the water around the plat smelled, and it would frequently change color (dark red).

Because of space constraints and steep cliffside, the train terminal for handling the finished coke was build on a cliff above the plant. This arouses a new problem, how to get the coke uphill to this new terminal? So, hey dug up another tunnel, this time a 750 m long one, which housed the rope way for transferring the coke uphill. All along the tunnel were piles and piles of finished coke left there after the plants closure.



We have been in many abandoned tunnels/bunkers in the past, but this one was one of the creepiest explorations to date. You get a strange vibe walking deep in a tunnel like this and seeing only darkness in the distance as you hear your every footstep.

There is a lot of thing we didn't get a chance to photograph, as our main objective was to film the exploration. If you are interested in the full history and footage, you can check out the full exploration:

Sometimes its easy to focus on what locations are rather than what they were. Posts like this, with historical photos and context surrounding a site's history, are a nice reminder that we're walking through history, not just photo opportunities.

Very interesting bit of infrastructure. Thanks for sharing.

I can't believe that underwater tunnel shows no signs of water infiltration despite not being maintained all these years. Kudos to whoever designed / sealed those joints.

The video ended kind of prematurely. Did you figure out how they got the coke up the cliff?

LOL at the furry friend inside the tunnel it scared the hell out of you guys

Posted by Emperor Wang Very interesting bit of infrastructure. Thanks for sharing. I can't believe that underwater tunnel shows no signs of water infiltration despite not being maintained all these years. Kudos to whoever designed / sealed those joints. The video ended kind of prematurely. Did you figure out how they got the coke up the cliff?

Yea, we found it fascinating too. If it wasn't so well sealed, it would gradually fill up with water with the smallest hole forming.

The cliff where we ended up going through the tunnel is right above the ex coke factory. They used a long ropeway which went up this cliff and through the tunnel, and you can even see coke ore scattered through the forest right below this line. As the ropeway was removed after the factory closed, there was nothing for us to see except dense vegetation, so we didn't go further.