The tranquil, pine-carpeted hills in this patch of southern Spain hold awful secrets. Now, one of them has been thrust into the spotlight of a divisive, emotionally wrenching drive to address atrocities committed in the Spanish Civil War.

At the start of the 1936-39 war, Viznar, near the ancient city of Granada, became one of many execution grounds for perceived opponents of Francisco Franco, the army general who unleashed the conflict by rising up against the elected, leftist Republican government.

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People were rounded up, brought here and shot, their bodies dumped in a ravine in unmarked graves — all for simply having been considered supporters of the government.

One of them was perhaps the war's most famous victim, Federico Garcia Lorca, widely considered Spain's best 20th century poet and playwright.

But while his executioners may have wanted to erase all memory of him, a lingering dispute over whether to open Garcia Lorca's grave is now a key focus of a movement to give proper burial to the untold thousands believed to have been murdered by Franco's militias.

Garcia Lorca was shot along with a school teacher named Dioscoro Galindo Gonzalez and two labor union activists — Francisco Galadi and Juan Arcolla — on Aug. 18, 1936 and their bodies are believed to be buried near an olive tree outside the town of Alfacar, close to Viznar.

Lorca, who was 38 when he died, is best known for tragedies such as "Blood Wedding" and his poetry collections "Poet in New York and "Gypsy Ballads." His work draws on universal themes such as love, death, passion, cruelty and injustice.

For years, the poet's descendants blocked requests by the Galindo and Galadi families to open up the grave. Tired of waiting, Galindo and Galadi relatives took their case to crusading investigative magistrate Baltasar Garzon, who had recently begun a probe into Spain's Civil War missing.

Garzon has spent years going after former military rulers accused of human rights abuses in far-flung nations like Argentina or Chile. In 1998, he famously issued an arrest warrant for former Chilean President Augusto Pinochet. Now, he is setting his sights on Spain's own murky past. He's treading sensitive ground, however, in a nation where both sides committed wartime atrocities but which tried to put all the suffering behind it in the interest of rebuilding from a war that left an estimated 500,000 dead.

The Franco regime carried out a thorough accounting of Republican militia killings of people seen as supporting Franco, and gave them proper burials. But those on the other end of the violence have had no such satisfaction.

"It's about time Spanish authorities took responsibility for this," said Emilio Silva, a former journalist whose quest to find the remains of his murdered grandfather a decade ago gave rise to a nationwide network of associations of people bent on similar missions.

Silva says that although Spain's Socialist government passed a watershed bill last year that formally denounced the Franco regime and made symbolic amends to victims, it basically pushed aside the issue of the missing. And it left families with no alternative but legal action.

Spanish conservatives complain that this law, the work of people like Silva and now Garzon's campaign are digging unnecessarily at old wounds.

In the Garcia Lorca case, at least, the pressure for closure appears to have produced results. Last week, the family unexpectedly announced it would not oppose any judicial order to exhume the poet's grave.

Nieves Galindo, granddaughter of the slain teacher, said she took the case to Garzon after 10 years battling to have his remains dug up, formally identified and given proper burial in his home town.

"My only desire is that each person should have their loved ones where they want them," she said.

The Garcia Lorcas say they would prefer the poet's bones to be left untouched and for the whole Vizar ravine area to be preserved as a historic monument to victims of Franco repression.

Garzon may take months to rule on whether to exhume the grave but it's clear that events which started as a painful trickle through Silva and others are now gathering momentum. So far these groups have managed to excavate some 160 mass graves and recover some 4,000 bodies, Silva said.

Garzon has asked church leaders, city mayors and other authorities for information about those killed outside of battle by Franco's forces from the time of his military uprising in July 1936. The goal is to compile a reliable list of victims.

Should he find there was a systematic campaign to kill Republican opponents outside the theater of war, he could order a full-blown investigation, although it is not known if he would seek indictments. So much time has gone by it is not clear who might still be alive for him to charge.

There is no official record of how many people died at the hands of Franco's forces during and after the war, although Silva and others presented Garzon Monday with the names of 130,000 people believed to have been summarily shot and dumped in unmarked graves across the country.

Historians say 55,000 people were killed by Republican forces.

At Viznar alone, up to 3,000 people are believed to have been killed by Franco forces. Plaques and stones with victims' names and inscriptions dot the area.

"Lorca Was Everyone" reads one stone while another, dedicated to a Granada University rector, says simply: "To another innocent victim of that madness."