Secret Cold War Balkan 'Bond' base opening to world

A visitor uses his flashlight as he walks inside a dark tunnel at the Zeljava underground army airbase in the heart of the Pljesevica mountain, on the Croatian border with Bosnia. Photo: AFP

Like something out of a Bond film, the giant Zeljava airbase was carved into a mountain between Bosnia and Croatia and designed to withstand a nuclear strike.

But for decades it sat idle, with only the occasional intrepid tourist daring to venture into its crumbling cavernous core.