Catalan firefighters have been battling flames day and night against a wildfire at the national park of Cap Creus in Girona, roughly two hours away from Barcelona.
350 people were evacuated from their homes as flames approached residential areas, firefighters said.
The area is a natural paradise attracting many tourists, especially during the peak summer season.
Over 400 hectares have already been lost to the wildfire that remained active on Saturday, according to regional authorities.
Interior councillor Joan Ignasi Elena visited the area on Saturday and called upon citizens to act responsibly.
"The fire was caused by a cigarette butt, and that is a shame," he said.
More than 200 firefighters are currently battling the flames, with the support of several helicopters and bomber planes.
Elena said French rescuers were called in to help.
Due to its hot and dry climate, Spain is often hit by major wildfires in summer. According to experts, the blazes risk becoming more frequent and destructive due to global warming.