The Fossar de la Pedrera is located on Montjuïc hill in the Sants-Montjuïc district of Barcelona. Forming part of the Montjuïc Cemetery, it was used as a mass grave for 4,000 victims of Spain's White Terror. There is now a memorial on the site.
Since 1985, the area also houses the remains of Lluís Companys, the 123rd President of Catalonia, who was executed nearby at the Montjuïc Castle by the Francoist government on 15 October 1940. His death is commemorated annually by Catalan politicians and civilians, who lay a wreath in memory of the president.
Wikipedia https://en.wikipedia.org/wiki/Fossar_de_la_Pedrera
Address Zona Franca Port 08038, Spain
Coordinates 41°21'21.243" N 2°8'54.609" E