A fire that started at 1:33 on Monday afternoon in the Monchique area was tackled by 130 firefighters with help from aerial support.
The flames tore through scrubland in the Ribeira das Canas area, near the county border with Portimão.
Strong winds hampered efforts to quell the flames but the fire finally was declared extinguished at 5:35pm.
The authorities said that no buildings were damaged or people injured, with the exception of one member of the GNR who received a slight wound.
Update
A 70-year-old British resident has been made an official suspect following the Monchique fire that destroyed 16 hectares.
The resident has asked permission to have a bonfire which got out of control as inadequate precautions had been taken.
