The city that never sees the light

Hundreds of kilometers of tunnels and bunkers have guarded the secrets of Madrid for centuries Some of them remain intact under public buildings

The entrance to a passageway that leads from the Royal Palace to the Campo del Moro gardens on its southern side.
The entrance to a passageway that leads from the Royal Palace to the Campo del Moro gardens on its southern side.BERNARDO PÉREZ

Few people are aware that Madrid was built on seven hills. Many kilometers of gloomy passageways and obscure tunnels have been drilled into them over the last thousand years. Where these underground galleries lead is known in some cases, but in many others the destination remains a mystery... That is, if they lead anywhere at all.

It is possible to visit some of these subterranean roads, while others allow visitors no further than the entrance. And even though they appear to meander randomly under the city, this way and that, nearly all of them had a practical purpose when they were built: some were shelters, others prisons, arsenals, archives, water canals, wine cellars or food storage deposits. In nearly all cases, the driving need was the same: keeping something valuable under wraps.

Up to 145 kilometers of subterranean water canals built by the Muslims beginning in the 10th century quenched the thirst of Madrileños until the 19th century, when they were sealed. Their vents, called capirotes, can still be seen inside the parks of Fuente del Berro and Dehesa de la Villa.

But the collective imagination associates many other passageways with secret escape routes out of convents, palaces, embassies and military barracks, of which there were more than 300 in the city center from the 15th century onward. For instance, there was the tunnel that linked the Vargas home on Plaza de la Paja with the Bishop's Chapel, and connected from there to dark, winding corridors leading to unknown parts of the city's belly in a westerly direction. In the 1970s, thieves used this very same tunnel to break into the crypt of the beautiful Gothic chapel and raid the tombs, which dated back to the late Middle Ages and contained crosses, swords, coats of mail and other knightly items of great value.

The entrance to the bunkers underneath the Finance Ministry.
The entrance to the bunkers underneath the Finance Ministry.BERNARDO PÉREZ

Another one of the best-known tunnels connected -- and still does, despite being in a derelict state as a result of construction work at Plaza de Oriente -- the convent of Encarnación with the former Habsburg Alcázar, a fortified palace that went up in flames in a terrible fire during Christmas 1734, and was the forerunner of today's Royal Palace.

The splendor of this passageway with wide galleries and lit by large torches was documented in the mid-17th century by the Pope's ambassador to Madrid, Nuncio Barberini, who also mentioned the works of art by court painters that decorated its walls. The tunnel began inside the kitchens of the old Alcázar and had several bends. Its essential function was for the king to be able to go to Mass at the monastery without having to go outdoors in the cold winter months.

An apocryphal legend has it that a section of this gallery was flooded and allowed the lascivious Phillip IV to go down this waterway to the monastery in a gondola to flirt with a cloistered novice who lived there. The king had become sadly notorious for harassing a young nun at the convent of San Plácido; the victim ultimately feigned her own death to escape from her royal pursuer.

In the west wing of the Royal Palace, overlooking the Campo del Moro, it is still possible to make out the trap door opening onto a passageway that represented an escape route from the palace gardens to the area now taken up by the Príncipe Pío train station. Another large tunnel that ran next to the gardens, and now buried following construction work on the M-30 beltway, was used by Joseph Bonaparte, Napoleon's brother - el Rey Intruso [the Intruder King], installed on the throne by the French emperor during the Peninsular War - to access the Vargas palace, which still stands near Puerta del Rey in the vast green expanse of Casa de Campo. This palace was an old hunting lodge where the royal impostor felt safer than in the palace, and where he used to take his pleasure with his lover, a renowned actress of the day.

Yet another underground maze near the Royal Palace, on the east side, acquired some fame because King Alfonso XII used it to go on incognito night outings through the city during his 10-year reign, from the mid-1870s to the mid-1880s (he died of tuberculosis aged 27). There was a little ditty about it that went: "Who is that good lad, who can he be, with that silk cape... He's not number one, he's not number two, he's number 12 by the grace of God."

One of the branches of this network of secret palace tunnels led to premises that would eventually become a restaurant called Torre-Narigües on Factor street.

One basement was used by Franco's Fifth Columnists' clandestine radio

It is also a known fact that the underground network under "Madrid de los Austrias" (Habsburg Madrid, a reference to the Austrian house that ruled Spain before the Bourbons) helped the notorious 19th-century bandit Luis Candelas make his getaways. Candelas had been a student at Instituto San Isidro, which still functions as an educational center. Its Baroque cloister shows evidence of the way into a secret corridor where, in a day of popular rage in the early 19th century, several friars were lynched by an angry mob after being accused of poisoning the nearby water fountains.

Politics, diplomacy and military action, which often require the cover of secrecy, were the driving forces behind many other underground spaces. On Alcalá street, on the ground floor of the Finance Ministry, there is something called Pasaje de la Aduana: it is a door with iron bars and a long ladder leading down to the underground room where the Socialist leader Julián Besteiro issued his message about troop rendition before the advancing forces of the rebel general Francisco Franco in late March 1939.

Not far from here, on Gran Vía, deep tunnels that have since been walled up perforate the ground under the building housing Unión Radio, the forerunner of today's SER network. That basement was used for a clandestine radio station that the so-called Fifth Columnists used to relay intelligence from the Republican rearguard to aid Franco's troop movements.

On Plaza de la Marina Española, under the Senate, there used to be a shooting range used by military personnel from a nearby 19th-century barracks. These premises were next to a building used by the Inquisition until 1820, and which itself had plenty of underground dungeons. The gallery under the Senate was used by the Spanish dictator as a bunker during the toughest part of his tenure, in 1946, when France closed down its borders with Spain, among other things because of Franco's alignment with Hitler and Mussolini during World War II, and also in protest over the execution of Cristino García Granda, a Spanish Communist guerrilla fighter and maquis who fought against the Nazis in France and was made a Chevalier de la Légion d'Honneur by the French state. Cristino was captured by Franco's police on Magallanes street along with several other guerrillas and executed following a summary court-martial. Those were the days when Franco feared that the Allies might try to depose him through military action.

The underground bunker used by the Socialists during the civil war siege of Madrid.
The underground bunker used by the Socialists during the civil war siege of Madrid.BERNARDO PÉREZ

Meanwhile, seven floors below the Bank of Spain, a dark, unused gallery contains a discreet set of railway tracks connecting the central bank to its subterranean security chamber. Just a few meters further off in a straight line, strange sounds began to issue from the basement of Casa de América two decades ago, fueling speculation about old forgotten stories that took place there long ago.

But one of the snazziest underground passageways in all of Madrid is located under Congress. Decorated with great luxury, it leads to the offices of parliamentary groups which are housed inside the former headquarters of the Banco Exterior de España. The tunnel crosses under Carrera de San Jerónimo and allows parliament's profuse bureaucracy to go just a little faster. Also under the enormous building used by the lower house, there are over 100 pillars made of brick and stone, up to five meters in height, that once held up the Church of the Holy Spirit.

Retired firefighters at the Puerta de Toledo station still remember how, years ago, every time there was a rainstorm in Madrid they had to go check certain sewers that flowed into the Manzanares river: they nearly always found a dead body or two that had been dragged there by the powerful subterranean tide. They were the corpses of well-cleaners who had been caught off-guard by the rising waters. These well-cleaners are the true, suffering inhabitants of these gloomy underground spaces.

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