The construction of the Basilica of the Valley of the Fallen took place between 1940 and 1958 by decision of the Head of State himself, Francisco Franco.

In the construction works, mainly free workers and prisoners participated, albeit to a lesser extent, between the years 1942 and 1950, under a system of sentence reduction through labor. The presence of these individuals was due to the organization of the Spanish penitentiary system, which included the "Work of Sentence Redemption through Labor", under the direction of a Central Board that collected voluntary requests from prisoners who wished to reduce their sentence time through this means, in addition to receiving a salary equal to that of free workers in the sector.

It was built in the 16th century under the mandate of the powerful King Felipe II, and conceived as a residence, monastery and pantheon of the Royal House, becoming a symbol of the greatness of the Spanish empire. - It has been declared a historical artistic ensemble, and World Heritage Site in 1984.