Crews working across the Canary Island of La Gomera said they were "finding it difficult to limit the spread of fire".
Wind and high temperatures has helped rekindle the flames in many areas, and forced the emergency services to retreat from the hills and mountains.
Officials in La Gomera said there was evidence that the fire was started deliberately. Ten towns and villages were evacuated across La Gomera, whilst residents and holiday makers had to flee eight towns across Tenerife.
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Rain spreading eastwards throughout the day.
"His fiancee gave birth this morning, of all mornings! We were scared because we've got Glastonbury tonight", said co-singer Chloe Rhodes.
Festival-goers have been enjoying the second day of the Glastonbury festival.