Three penal detachments were formed to build the monument, using political prisoners, who worked there between 1943 and 1950. Testimonies to the lives of these prisoners have been collected by journalists Daniel Sueiro and Fernando Olmeda, and further details have emerged in the memoirs of prisoners themselves, such as Américo Tuero and Nicolás Sánchez-Albornoz. Archive documents are also plentiful.
Nonetheless, many aspects of daily life remain to be explored. Archaeology offers one way to learn about some of the lesser known aspects, including the experiences of groups and individuals to whom scant attention has so far been paid, such as the women and children who lived at Cuelgamuros.
In May 2021, the Spanish Institute of Heritage Sciences conducted an archaeological dig at the Valley, funded by the Office of the Secretary of State for Democratic Memory. It had a dual purpose: to further knowledge of the lives of the prisoners, free workers and their families, and to shift the focus of attention to the people who built the monument. The findings have proved fruitful.
About eighty huts have been located, where families (and sometimes free workers) lived. They were found in the penal detachments belonging to San Román – the company commissioned to build the Basilica – and Banús – which was responsible for the road and viaduct. The foundations of the barracks were also found, including a disinfestation chamber where the prisoners arriving from the overcrowded postwar jails were treated for parasites.
The best preserved detachment is in the Banús sector, where seven huts have now been excavated, offering an eloquent picture of life in Cuelgamuros. The stone huts were very small (four to nine square metres), without sanitation, running water or electricity. They had earth floors or granite slabs, and roofs made from branches. The items found inside and in nearby rubbish dumps are indicative of the hardship experienced: the absence of animal bones and the presence of food supplements suggest a poor diet; medicines indicate the diseases from which they suffered, particularly gastrointestinal and bronchopulmonary conditions; the many makeshift objects like lamps, tools and braziers made out of tins, or the soles of their shoes made with old tyres suggest both scarcity and the skills that inhabitants had to develop in order to survive. Prisoners and their families appear to have cooperated with one another, building similar huts and improvising household items, learning from each other and working together.
Archaeological analysis of the materials left behind leave us in little doubt that life in Cuelgamuros was hard, but that a spirit of resistance and solidarity nevertheless prevailed under these harshest of working conditions and deprivation of freedom.