Washington, March 26 : A tunnel network has been uncovered beneath the historic heart of the Maltese capital of Valletta, which according to rumors, had been constructed by the crusading Knights of the island of Malta.

According to a report in National Geographic News, the newfound tunnels date back to the 16th and early 17th centuries, when the knights—one of the major Christian military orders of the 11th- to 13th-century Crusades—fortified Valletta against Muslim attack.

The tunnels were uncovered on February 24 during an archaeological survey of the city’s Palace Square in advance of an underground-garage project.

“A lot of people say there are passages and a whole new city underground. But, where are these underground tunnels? Do they exist?” said survey leader Claude Borg of the Valletta Rehabilitation Project.

“We’ve now found some of them, at least,” he added.

The tunnels were found beneath Palace Square, opposite the Grandmaster’s Palace. Once home to the leader of the Knights of Malta, the palace today houses Malta’s legislature and the office of the Maltese president.

First, workers found what’s believed to have been an underground reservoir just under the paving stones of Palace Square.

Near the bottom of the reservoir, some 40 feet (12 meters) down, they discovered a large opening in a reservoir wall—the entrance to a tunnel, which runs half the length of the square and connects to channels, some of which lead toward the palace.

“Efforts to follow these branches have so far failed, as they were blocked off at some later date,” Borg said.

According to restoration architect Edward Said, of the Fondazzjoni Wirt Artna (Malta Heritage Trust), the discovery is “just the tip of the iceberg.”

Said suspects the tunnels formed part of a state-of-the-art plumbing system, complete with ancient passageways for access and maintenance.

Other rumors of underground Valletta include a secret carriageway from the city to the palace of the Roman Catholic inquisitor—charged with rooting out heretics—under Valletta’s harbor.

Such tales of secret military passages have more solid foundations, according to Said, since underground passages do run beneath the battlements protecting Valletta’s landfront.

Also known as the Knights Hospitaller and the Order of St. John, the Knights of Malta, established in 1099, gained a formidable military reputation as enemies of Muslims during the Crusades, a series of Christian military campaigns that originally had the goal of capturing Jerusalem. (ANI)