The fires in Spain this year have burned 158,000 hectares or 610 square miles, according to the European Union’s European Forest Fire Information System. That is an area roughly as big as metropolitan London.

Firefighters in Spain, Portugal and Greece battled ongoing wildfires Friday, an important religious holiday in all three countries, as persistent hot, dry conditions challenged efforts to contain the blazes.

By Michael Francis Gore, Charlie Devereux and Ana CanteroVILLANUEVA DE LA SIERRA, Spain (Reuters) -Spain battled 14 major fires driven by high winds and aggravated by heat on Friday as authorities warned of "unfavourable conditions" to tackle flames that have already killed seven people and burned an area the size of London.

Hundreds of firefighters battled to put out wildfires across southern Europe on Thursday, some of which are believed to have been set deliberately by arsonists and stoked by an extended heat wave gripping the region.

Wildfires intensified across southern Europe on Wednesday with a round-the-clock battle to protect the perimeter of Greece’s third-largest city and at least three deaths reported in Spain, Turkey and Albania.

Images from Portugal, France, Greece, and other places in the region where a searing heat wave and strong winds have spawned destructive wildfires for the past two weeks. Thousands of firefighters and volunteers are battling the deadly blazes,