
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. (Photo: Reuters)

The compound, hidden under the picturesque port city perched on cliffs above the sea, was built by the British and served as the staging ground for major naval operations. The British military withdrew in 1979 and the compound was abandoned for almost 40 years. (Photo: Reuters)

Graffiti left by vandals covers the walls in the Briefing Room at the Combined Operations Centre, dating back to World War Two, in the War Headquarters tunnels beneath Valletta, Malta. (Photo: Reuters)

A reel of cine film is seen in the NATO tunnels dating back to the Cold War in the War Headquarters tunnels beneath Valletta, Malta. (Photo: Reuters)

German and Italian forces bombarded Malta intensively between 1940 and 1942 to try gain control of the Mediterranean, but did not manage to force the British out. During the Cold War, the tunnels were used to track Soviet submarines. (Photo: Reuters)

Bed cots are seen in a restored area of the Combined Operations Centre, dating back to World War Two, in the War Headquarters tunnels beneath Valletta, Malta. (Photo: Reuters)

A detail on a map is seen in the map room at the Combined Operations Centre, dating back to World War Two, in the War Headquarters tunnels beneath Valletta. (Photo: Reuters)

Pigeon feathers lie on broken pieces of a wall map in the Briefing Room at the Combined Operations Centre, dating back to World War Two, in the War Headquarters tunnels beneath Valletta. (Photo: Reuters)

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. (Photo: Reuters)

Malta is now restoring the 28,000 square metres (300,000 square feet) of tunnels, planning to open a huge section to the public. (Photo: Reuters)

A staircase leads upwards at the NATO tunnels, dating back to the Cold War, in the War Headquarters tunnels beneath Valletta, Malta. (Photo: Reuters)