A strike by archaeological site guards will shut down the Acropolis, the country’s most visited monument, for six days, their union said yesterday. The ancient citadel, which contains architectural marvels such as the Parthenon and the Temple of Athena Nike, will remain closed tomorrow and Sunday and then again between July 21 to 24. Union officials said the move was aimed at pressing the Culture Ministry to satisfy their demands on working conditions and pay. «Given that despite assurances, no response has been given to our demands, we decided to go on strike,» said the Archaeological Guards’ Union, which numbers some 1,900 members. The guards want better pay for night duty and for working six days a week, among other demands.