New Croatian TV series explores Cold War bunkers, secret tunnels and abandoned military bases

(Photo: Press)

A new four-part Croatian adventure documentary series is taking viewers deep underground to explore some of Europe’s most remarkable remnants of the Cold War.

Ispod radara (Under the Radar), produced by Creative Objective for Croatian Radiotelevision (HRT), travels through former military installations, underground bunkers, command centres and secret tunnels in Croatia, Bosnia and Herzegovina, Albania and Sweden.

The series examines how different countries prepared for a conflict that ultimately never unfolded in the way planners had anticipated, and what happened to the vast infrastructure left behind.

During the Cold War, Sweden built shelters designed to protect millions of civilians. In the former Yugoslavia, the ARK D-0 underground complex near Konjic was constructed deep inside a mountain for Josip Broz Tito and a select group of political and military leaders.

Albania took a different approach under communist leader Enver Hoxha, with more than 170,000 bunkers estimated to have been built across the country.

(Photo: Press)

Decades later, many of these sites have acquired a new life as museums, tourist attractions, cultural spaces or, in some cases, abandoned structures.

The series is presented by geographer and GIS specialist Lidija Kožar and pilot, adventurer and urban explorer Josip Kovač Levantin. Together, they enter locations that once had highly restricted access, travelling by aircraft, quad bikes, motorcycles and, in some cases, ropes into underground spaces.

(Photo: Press)

One of the central locations is the former Željava underground airbase on the Croatia-Bosnia and Herzegovina border.

The presenters are joined there by Croatian pilots Danijel Borović, Ivan Selak and Ivica Ivandić, who served at the base in the late 1980s. They return to the complex more than three decades later, offering first-hand accounts of a facility that once housed aircraft, technical crews, command centres and other infrastructure deep inside the mountain.

The enormous reinforced doors protecting the base were designed to withstand a potential nuclear attack.

The series also visits Albania, where an extensive underground complex beneath Kukës includes tunnels, a hospital, bakeries, a printing facility and its own energy system.

In Sweden, the programme explores Pionen, a former Cold War-era underground facility that now houses servers, as well as Aeroseum, a former underground military airbase near Gothenburg that has been transformed into an aviation museum.

The programme also focuses on the people connected with these places.

At Gola Plješevica, former serviceman Gordan Jelača returns to the location where he served decades ago, this time accompanied by his son. At Željava, former pilots revisit a place that was once their workplace rather than the abandoned ruin it has become today.

(Photo: Press)

The series is directed by Luka Tokić, who also co-wrote the script with dramaturge and screenwriter Tea Matanović. The concept was developed by architect and urban exploration pioneer Mihovil Pirnat.

Rather than presenting the Cold War solely through historical narration, Ispod radara uses the physical remains of the period to explore how these places were designed, how they operated and what their future could be.

(Photo: Press)

Pirnat has documented abandoned civilian and military sites since 2008 and highlights the growing challenge of preserving or repurposing such complexes as time takes its toll.

Ispod radara airs on Mondays at 21:35 on HRT’s First Programme, with missed episodes and repeats available on HRTi.