Beneath your feet, several metres down, run brick galleries from colonial times. They're one of the great riddles of Buenos Aires: everyone knows they exist, but not why they were built.

1What the records say

The tunnels already appear on a map from 1780, which shows they existed in the colonial period. A newspaper report in 1848 and a study by the naturalist Hermann Burmeister in 1893 mentioned them again. In 1912 the ground caved in on calle Perú, and researcher Héctor Greslebin seized the chance to study them. In 1974 another collapse at Alsina and Bolívar exposed some 70 metres of tunnel.

2Three theories

No one has found the document that explains what they were for. Three ideas have been put forward:

  • Defence: an escape route or a link to the fort in case of attack.
  • Communication between churches and buildings in the area.
  • Smuggling: a discreet path for goods in a city that lived off illegal trade.
Historian Ruth Tiscornia rejected the defence theory. The debate is still open, and in 2023 restoration work uncovered new cisterns and conduits.

Popular imagination has done the rest: there's talk of tunnels reaching the river or linking every church downtown. No study has ever proved it.

3What to look for

  • The gateway on calle Perú, entrance to the complex and its underground visits.
  • San Ignacio church, the oldest in the city, standing over the tunnels.
  • The street level: picture galleries more than two hundred years old under the asphalt.

Documented

The tunnels exist, appear on a 1780 map and were studied in 1893, 1912 and after the 1974 collapse.

Oral tradition

The belief that the tunnels reached the river or linked every church downtown is popular lore, never proven.

Sources and credits

Manzana de las Luces Cultural Complex (Argentine Ministry of Culture); Spanish Wikipedia, «Manzana de las Luces»; Daniel Schávelzon, Túneles de Buenos Aires (Sudamericana).

Photos:

  • Colonial building of the Manzana de las Luces at the corner of Perú and Alsina: Roberto Fiadone, CC BY-SA 3.0.

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