Valle de los Caidos (Cuelgamuros), Madrid. The bodies of 12,410 unidentified Republicans, victims of Francisco Franco, were transferred here without the knowledge of their families. (Miquel Gonzalez)

Barranco del Carrizal II, Orgiva, Granada. On Aug. 11, 1936, Manuel Lopez Lopez, deputy mayor of Lanjaron, and his sons Antonio and Felix, were shot by the Guardia Civil and Falangists and disappeared here. Some 4,000 people were killed and buried in quicklime in this ravine. (Miquel Gonzalez)

Miquel Gonzalez, a photographer with Spanish roots living in Holland, became frustrated at the lack of memorials at the sites of atrocities committed against the Spanish people during the Spanish Civil War and under the repressive regime of Francisco Franco. According to Gonzalez, as many as 114,000 bodies of those killed during that period in Spain’s history are still in unmarked mass graves on the edges of towns and villages. Many of the sites have been lost or forgotten, and some have been covered up by new construction, erasing any sign of the past. Spurred by his frustration, Gonzalez spent three years traveling Spain, searching for what he calls its “lost memory.”

Traversing Spain, Gonzalez visited mass gravesites as well as related atrocity sites. Of the project, Gonzalez said:

“I intended to approach the atrocity sites as neutrally as possible and to respond to what I would find and feel. I captured the places as close to the same hour, day and season of the year of the killings as possible. Most photographs were taken after sunset and before sunrise, the preferred hour for “walking” and executing people. The emptiness and silence that caught me when visiting the sites gives a certain serenity to the landscapes, in strong contrast to the horrors which occurred there. Whilst the sites were impregnated with human traces, it was the human absence that struck me the most. It made me think about the victims and somehow reestablished their presence into the empty landscape.”

The resulting work is a haunting collection of visual memories that now makes up a book, “Memoria Perdida: Spains’ Lost Memory 1936-1975,” which can be bought here.

Viznar II (Barranco de Viznar), Granada. Pharmacist and feminist Milagro Almenara Peréz, 36, was murdered on Nov. 2, 1936, along with Rosario Freqenal Pinar, Rosa Sequra Calero and Concha Pertinez Tabasco between Viznar and Alfacar. (Miquel Gonzalez)

Viznar IV (Llanos de Corbera), Granada. This area had open wells and a shooting range during the years of repression. There may be 400 victims at the bottom of these wells. (Miquel Gonzalez)

Montes de Torozos II, Valladolid. This monument to the victims of the Franco regime has been vandalized several times in the past. In 2013, a section of the new highway linking Valladolid and Leon was inaugurated. The engineering work came very close to the area. (Miquel Gonzalez)

San Andres, Santa Cruz de Tenerife. On this coast, victims of reprisals were thrown into the sea in sacks weighed down with stones, sometimes while they were still alive. (Miquel Gonzalez)

Monte de Estepar II, Burgos. More than 300 people were shot here between August and October 1936. They were “taken for a walk” from the Burgos prison and executed. (Miquel Gonzalez)

O Amenal II, O Pino, La Coruña. Five municipal council members of Boimorto, Caitan García Vazquez, Isidro and Andres Filloy Lopez were killed on the side of the road on Aug. 20, 1936. (Miquel Gonzalez)

Villalibre de la Jurisdiccion I, Leon. 1936-37. Arsenio Macias, 16, was killed by Falangists because he refused to reveal the whereabouts of his older brother Claudio. (Miquel Gonzalez)

Montearenas (A-6 motorway), Ponferrada, Leon. The motorway construction entailed the loss of several mass graves. There were 60 documented murders in the area, but there may be more than 200. Bernabe Gonzalez Canas, 29, was shot and buried in a mass grave on Sept. 20, 1937. (Miquel Gonzalez)

San Juan de Ortono III, Ames, La Coruna. Six corpses were recovered by a priest and buried in a common grave. To this day, the bodies have not been recovered. (Miquel Gonzalez)

Campo de la Bota I, Barcelona. Between 1939 and 1952, 1,717 people were shot at the Campo de la Both by the Franco regime. The bodies would later be thrown into the Fossar de la Pedrera. (Miquel Gonzalez)

Cementerio de San Jose, Granada. Manuel Carmona Ruiz, 35, a metallurgist and trade unionist, was accused of illegal possession of weapons and executed here on Aug. 15, 1936, at 5 a.m. Between 1936 and 1956, 3,969 people were executed along the walls of the cemetery. (Miquel Gonzalez)

Castuera III (concentration camp), Badajoz. From April 1939 to March 1940, hundreds of prisoners were executed in the camp or “taken for a stroll” and shot by Falangist groups in the area. (Miquel Gonzalez)

Castuera II (concentration camp), Badajoz. The Gamonita mine shown here and other mines around the concentration camp are believed to contain the remains of hundreds of victims. (Miquel Gonzalez)

In Sight is The Washington Post’s photography blog for visual narrative. This platform showcases compelling and diverse imagery from staff and freelance photographers, news agencies and archives. If you are interested in submitting a story to In Sight, please complete this form.

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