Porn film stars frolic on Franco's big monument

The valley of the Fallen, an immense monument built by the dictator Francisco Franco as a mausoleum for himself and tens of thousands of the war dead, has long stoked passionate debate in Spain. The artificial granite ridge outside Madrid was carved by political prisoners on the losing side of the Spanish Civil War. For many Spaniards today, the surging 500ft cross which tops it is the most flagrant symbol of Franco-era repression.

But now this sombre site has aroused controversy for an unlikely reason: its use as a location in the filming of a satirical pornographic movie, Antonio Ramirez, the Fascist, set in 1960s Spain.

The plot revolves around a visit by the protagonist Antonio, his wife, his daughter, a maid and their "red" neighbour, to Franco's mausoleum, where thousands of Civil War victims are buried – often, in the case of the losing Republicans, against their families' will.

"The Fascist is not an ordinary pornographic film," boasts the film's distributor in a racy internet catalogue. "It is a parody of the years of Spain's political transition."

Extreme right-wing groups were outraged to learn that the movie-makers were allowed to film sex scenes on location. Filming took place in 2007 – the year Spain's Socialist-led government banned fascist meetings at the site.