In a vast network of tunnels carved into the rocks under the Maltese capital Valletta, faded maps of the Mediterranean hint at the place's role in directing key battles in World War Two.
Malta is now restoring the 28,000 square metres (300,000 square feet) of tunnels, planning to open a huge section to the public.
Over the years, water and humidity have let rust and mould spread. Some rooms have been vandalised, but traces of the military apparatus that once occupied the complex still remain. Military cot beds, tangled cables and dust-covered rotary phones litter the rooms.
The Malta Heritage Trust, a non-governmental preservation group, began the multi-million dollar restoration of the site in 2009.