Talk of a maze of underground tunnels beneath the Colonial city of Puebla in Mexico were long disregarded as mere urban legend. However, last year, city authorities confirmed that their existence was no myth, as subterranean tunnels dating back as early as 1531, when the city was first founded, were unearthed and found to extend as far as 10 kilometers (6.2 miles). Now new investigations of the underground network have begun to unravel the secrets of Mexico’s hidden tunnels.

Discovery of Hidden Tunnel Network

In September, 2015, El Universal reported that the underground tunnels, which measure approximately 7 meters (23 feet) high and 3 meters (9.8 feet) wide, were discovered during public works being carried out in the city center. Four separate entrances were found filled with earth. After removing tons of earth and mud, investigations revealed a line of tunnels running from Fort Loreto to the Fort of Guadalupe in the upper part of town, and from Fort Loreto to the District of San Jose, located in the center of the city. A third line was discovered from the Fort of Guadalupe to Los Remedios Church, where the defense of Puebla took place against the invading French Army in 1862.

"In the urban narrative or urban legends there was word of the tunnels in Puebla, but nobody knew where they were, they had never been seen", the manager of Cultural Heritage and Historical Center of Puebla, Sergio Vergara Bermejo, told El Universal.

A Secret Beneath a Historic City

Founded in 1531, Puebla is one of the oldest cities in Mexico and is among the five most important Spanish colonial cities in the country. Due to its rich history and its impressive architectural styles, Puebla was named a World Heritage Site in 1987. Stories of underground tunnels were passed down through the generations, but were long considered an urban legend until their discovery last year.

“Puebla in the seventeenth century was flooded and half the city was covered in mud, the city we walk is the eighteenth and nineteenth century, the bottom are the treasures that we must preserve,” said Bermejo.

The mayor of Puebla, Tony Gali, earmarked 5 million pesos (approx. U.S. $295,000) for the excavation and restoration of the tunnels.

Shedding New Light on Puebla’s Subterranean World

El Pais reports that local government officials in Puebla have been investigating the tunnels ever since their discovery with the aim of shedding some light on their history.

“The passageways feature different architectural styles, reflecting the time of the construction,” writes El Pais. “So far, 15 different archway systems built to support the structures have been found. For example, builders used a type of cement composition made with stone chips and other materials to fashion a half-way arch.”

Remarkably, the underground structures have withstood the weight of the buildings above, water systems, and earthquakes over the centuries, and remain in good condition.

During the restoration of the underground tunnels investigators also found the ancient remains of the Puente de Bubas, a bridgelike structure from the 17th century that was used to cross the San Francisco River, which was the main water source for the city in that era. (Credit: Saúl Sánchez )

Transporting Treasures and Supporting War Efforts

It is now known that the tunnels were initially utilized by the Catholic Church. Built around the same time as the majority of churches and monasteries in the city, the subterranean roads became a way for the Church’s treasures to be safely transported from one place to another.

Later, the tunnels supported the city’s war efforts against the French Army in the famous Battle of Puebla, in 1862.

“The details support the theory that the underground passage was used to transport weapons, ammunition and soldiers during the now-commemorated battle that took place on May 5, 1862 when Mexicans repelled an invasion of French soldiers sent by Napoleon III,” reports El Pais. “The tunnels were also used to attack the French on different fronts at the time of the invasion.”

Reviving the Ancient Tunnels

The plan is to transform the recently-discovered subterranean world into a tourist attraction so visitors can learn more about the stories and legends of this historic city.

The entrance to the first of nine tunnels – called the Puerta de Zaragoza – will be opened to visitors in February.

Featured image: Newly-discovered tunnels in Puebla. (Screenshot from YouTube video / The Telegraph )

By April Holloway