Passengers rest surrounded by rubbish and papers thrown by cleaning workers as they hold the fourth day of a strike at Barcelona airport in Prat Llobregat, Spain, Thursday, December 1, 2016. (Photo by Manu Fernandez/AP Photo)





Passengers walk surrounded by papers thrown by cleaning staff in a protest as they hold the fourth day of a strike at Barcelona's airport in Prat Llobregat, Spain, Thursday, December 1, 2016. (Photo by Manu Fernandez/AP Photo)





Passengers pull their suitcases as the floor is littered with pieces of paper during a protest by the cleaning staff at Barcelona's airport, Spain, December 1, 2016. (Photo by Albert Gea/Reuters)





Passengers walk in front of AirEuropa check-in desks as the floor is littered with pieces of paper during a protest by the cleaning staff at Barcelona's airport, Spain, December 1, 2016. (Photo by Albert Gea/Reuters)





Passengers check their mobile devices as a bin is full of garbage during a protest by the cleaning staff at Barcelona's airport, Spain, December 1, 2016. (Photo by Albert Gea/Reuters)





Passengers check their mobiles as garbage is accumulated during a protest by the cleaning staff at Barcelona's airport, Spain, December 1, 2016. (Photo by Albert Gea/Reuters)





Passengers queue in front of Vueling check-in desks as the floor is littered with pieces of paper during a protest by the cleaning staff at Barcelona's airport, Spain, December 1, 2016. (Photo by Albert Gea/Reuters)





A passenger checks his mobile as garbage is accumulated during a protest by the cleaning staff at Barcelona's airport, Spain, December 1, 2016. (Photo by Albert Gea/Reuters)





Passengers pull their suitcases as the floor is littered with pieces of paper during a protest by the cleaning staff at Barcelona's airport, Spain, December 1, 2016. (Photo by Albert Gea/Reuters)





A passenger walks past a bin full of garbage during a protest by the cleaning staff at Barcelona's airport, Spain December 1, 2016. (Photo by Albert Gea/Reuters)