Red and yellow danger flag at the beach, Praia Do Tonel, in the Alentejo region, Sagres, Portugal

red yellow danger flag beach cliff praia do tonel alentejo region sagres portugal waving flag beach safety warning signs coastal area water conditions safety measures maritime safety beachgoers alentejo coastline coastal destination lifeguard water safety tourist beach on duty surfing spot ocean conditions lifeguard services sagres coastline rocks dangerous currents beachgoer awareness sagres attractions coastal environment swimming conditions maritime activities alentejo beaches seaside resort hazardous waves alentejo coast coastal vacations ocean currents waterfront view do tonel beach clear sky