Zeljava Airbase is one of those places that sticks with you. Back in 2018, when I visited for the first time, it felt like stepping into a forgotten world. The entrance was blocked by a border patrol jeep, the kind of situation where you’re never really sure if you should even ask to pass. But we did, and to my surprise, the officer barely reacted—just moved the jeep and waved us through like it was nothing. That set the tone for the day. There was no one else around, just us, the endless runways, and the shadows of Mount Plješevica looming over everything.
The airbase, also known as “Objekt 505,” was built in the 1960s during the Cold War. It was no ordinary base—it was a fortress, buried under a mountain and designed to withstand nuclear attacks. Inside, MiG-21 jets could be launched straight from its tunnels, and it was self-sufficient enough to operate for a full month with no outside contact. It was state-of-the-art, built for a world on edge, but its story didn’t end as intended. By the 1990s, the Yugoslav Wars had torn the region apart, and the airbase was destroyed by the very army that built it to ensure no one else could use it. What’s left today is a sprawling, crumbling site—half war zone, half time capsule.
Walking around Zeljava in 2018 was surreal. The runways seemed to stretch forever, cracked and overgrown but still commanding in their scale. The tunnels, though, were something else. Stepping inside was like stepping into the unknown. They were damp and pitch black, the kind of dark that swallows even a strong flashlight. Every sound echoed—our footsteps, the occasional drip of water, and nothing else. It felt like the past was holding its breath.
There were no other visitors back then. No guides, no Instagramming tourists, no signs to point the way. Just the silence and the enormity of the place. It was hard to wrap your head around the fact that this had once been a hub of military activity. The stillness only made it feel bigger.
At the time, there were two old RF-84G Thunderjet planes sitting near the entrance. They were rusting and battered, but they had a presence—like sentinels watching over the site. Those planes are gone now, moved to Airport Otočac for preservation. It’s good that they’re being looked after, but their absence leaves a noticeable gap. It’s one less piece of the puzzle for anyone visiting now.
Fast forward to today, and Zeljava isn’t quite the secret it used to be. More and more people are finding their way there, and some parts of the site have been cleaned up or made safer for visitors. The raw, untouched vibe it had in 2018 is fading a bit, but even with the changes, it’s still an incredible place to explore.
If you’re planning to visit, keep in mind that it’s right on the border between Croatia and Bosnia, so make sure to bring your ID or passport. The tunnels, while amazing, can be dangerous. Some areas are unstable, and there’s always the risk of unexploded ordnance if you stray too far from the main paths. Stick to the safer areas unless you really know what you’re doing. A strong flashlight and sturdy shoes are essential—this isn’t a place for flip-flops and phone torches.
Even with the growing crowds, Zeljava still has an atmosphere that’s hard to describe. It’s not just about the scale of the place or its Cold War history—it’s about the sense of stepping into another time. Back in 2018, it felt like the kind of spot only the truly curious would find, a place that rewarded those willing to take the time to dig into its story. Now, it’s easier to get to and more widely known, but it hasn’t lost its ability to impress. It’s still Zeljava, and it’s still worth going.
