New Delhi, July 24 -- PARIS - At the height of the summer tourist season, when the campgrounds and riverside villages of southwestern France fill with holidaymakers from across Europe, the fires came again.

More than 20,000 people were evacuated in southwestern France on Wednesday as wildfires driven by temperatures exceeding 40 degrees Celsius swept through areas popular with tourists, BBC News reported. Campsites emptied as holidaymakers loaded cars and followed emergency service instructions to leave. The scale of the displacement, arriving at the peak of the travel calendar, injected immediate urgency into what is becoming a familiar annual crisis for this corner of the continent.

The fires struck a region that has not forgotten 202...