On 12 July 1979, Zaragoza became the site of tragedy, as the city's five-star Corona de Aragón hotel was engulfed in flames. More than 70 people lost their lives to the fire, and scores more were hospitalised, suffering grave injuries as a result of burns and inhalation of smoke.
Among distinguished guests staying at the Corona de Aragón on 12 July were Franco's widow Carmen Polo, her daughter and son-in-law and key military figures. The Academia General Militar, Zaragoza, was due to celebrate the inauguration of the new second lieutenants that day, among them Franco's grandson, Cristóbal Martínez Bordiú.
The first reports of the flames were received by the fire brigade around 6am. The blaze was declared under control before 9.30am. By then, however, the damage had been done, and the ten floors of the 237-room hotel were destroyed. Firefighters later described their main challenge as the panic of those trapped inside, as many leapt out of the windows in desperation, despite loudspeaker calls for guests to remain calm until help arrived.
Condolences poured in, as King Juan Carlos lamented the "terrible tragedy" and wished for the quick recovery of all involved. Elías Yanes Álvarez, Archbishop of Zaragoza, too made his rounds, visiting hospitalised hotel guests who had fallen victim to the flames. On 13 July, more than 3,000 people paid their respects to the dead at a funeral at Zaragoza Cathedral.
Investigation into the blaze pronounced the tragedy accidental; 20 litres of oil had caught fire in the Formigal 'churros' café on the hotel's ground floor. The notable hotel guest list on 12 July means that the cause of the flames remains to this day, however, a source of controversy. Local newspaper, Heraldo de Aragón, received two calls claiming responsibility in the hours following the disaster: one allegedly from Basque separatist organisation, ETA, and the other from anti-Francoist, revolutionary organisation, FRAP. Details of the investigation were not openly disclosed, and suggestions of terrorism have since been suppressed by judiciary officials. Speculation sparked by conflict continues however, and in 2000, relatives of those who had died started to receive benefits as victims of an attack.
A ruling on the prevention of fires in tourist establishments was passed in response to the Zaragoza tragedy on 25 September 1979.