The streets of Valletta are a tightly-packed grid of golden towers, shading the flagstones from the Mediterranean sunshine. But beneath its large public squares, elegant townhouses and grand palaces lies a secret subterranean world, undetected by many visitors but intimately known by the locals.
To understand why Valletta has a mirror image of itself underneath the surface, you must first understand Malta’s history. Lying at the midpoint between East and West Mediterranean, this limestone kingdom was strategically important to any colonizing power in the region. Crusaders, the Ottomans and the British Empire have all sought to take advantage of it, trying to claim the islands by force, diplomacy, or both.
Valletta, guarding one of the deepest harbors in the Mediterranean, is the key to the archipelago. The Knights of St. John (or Knights Hospitaller) arrived on the islands in 1530, and proceeded to build a beautiful, fortified capital to suit their lofty ideals. However, they’d lost two of their previous capitals – Jerusalem and Rhodes – to sieges by Mamluk soldiers and Ottoman invaders. With the Ottomans hot on their heels, it looked as if the Hospitallers were about to lose another one.
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In 1565, an Ottoman fleet under fearsome commander Dragut sailed onto the scene. They seized Fort St. Elmo, at the very tip of today’s Valletta. In the process, both the Ottomans and the Knights begun to dig tunnels underneath the fort. The limestone Malta sits on is soft yet dense, making it ideal for constructing caverns in a hurry.
Occasionally, the two sides would break into each other’s tunnels. It’s said that the diggers took up pickaxes, hammers and spades and fought each other hand-to-hand in the darkness. This is the first recorded instance of tunnels being constructed beneath Valletta. The Great Siege of Malta wore on for nearly four months. With the world watching, the Knights Hospitaller (joined by some 400 Maltese civilians) somehow repelled the siege, and clung onto the islands.
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Shortly afterwards, it was decided to improve Valletta’s readiness for future attacks. In 1566, the first reservoir was built, storing fresh water within the city walls to hydrate the residents of the besieged city. 12 cisterns were built, able to support 40,000 people for four months; the largest (several stories deep) still lies under Great Siege Square in Valletta. Niches and cellars cropped up all over the city, so dried food could be kept in reserve. Tunnels within Fort St. Elmo also emerged, so defenders could rush to and from the bastions without being attacked.
It wasn’t just siege tunnels that the Knights built. They also ordered the construction of vast, gridded drainage systems, far in advance of any other European city at the time. However, by the time the British took possession of Malta in the mid-19th century (and after a plague had wiped out 8,000 people in 1813), the drains were not fit for purpose. The new colonizers set about upgrading it.
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They also added another layer to Valletta’s secret underworld: a subterranean railway. Built in 1883 and running from Valletta to the suburb of Floriana and beyond, the underground rail transported commuters and goods across the island of Malta. It fell into disuse by the 1930s, but during the Second World War, it was used as an air raid shelter for 5,000 people. However, with only one toilet to go around, many of Valletta’s citizens preferred to dig their own bunkers underneath their homes.
Aerial bombing was a mainstay of Malta’s experience in World War II, being subjected to 3,000 raids by Italian, then Axis, forces. Men, women and children hastily built shelters beneath their houses and businesses, filling them with supplies and even personal touches, such as religious icons and wine bottles. Most were able to hold a family of four, and strung up with electric lights.
As well as the ad-hoc family shelters, the wartime government of Malta built a network of passages known as the Lascaris War Rooms, which were prepared for all eventualities. It had links to the sea and air defenses of the islands, and it was within these yellow walls that the 1943 Allied invasion of Sicily was plotted. They were used throughout the Cold War, too, as a means of intercepting Soviet submarines in the Mediterranean. Today, you can take a virtual tour of the War Rooms.
Though the War Rooms are refurbished and open to the public, most of Valletta’s underground network remains forgotten and unexplored. While locals will talk of secret passages and basements in their homes, hiding places passed down through the generations, piecing together the network in full has been difficult.
Aerial photos offer clues: In this cramped city, open spaces usually exist because the ground beneath it is too unstable to build on. This is certainly true of the squares built on cisterns, and the parks atop the old railway line. Architectural digs also bring up evidence—in 2009, work on a new subterranean parking garage revealed an extensive underground network, and revived local interest in the tunnels.
Some of the tunnels are being renovated for eventual public access, yet most remain undetected. The silent, snaking channels that were once the lifeline of this beleaguered city are abandoned for now, but they lie in wait, should Valletta ever need them again.