All archaeological sites and most museums in the Greek capital, including Athens' famed Acropolis, will remain shut Thursday morning due to a strike by site guards demanding the payment of overtime and the hiring of more staff.

The three-hour work stoppage starting at 8 a.m. (0500 GMT) comes at the height of Greece's lucrative tourist season. Museums and archaeological sites are two of the main attractions for the millions who visit the country each year, particularly during the summer.

The employees' union is demanding the payment of overtime for work on Sundays and national holidays, and the immediate hiring of 200 extra guards, which the union described as a "national urgency" for the safety and smooth functioning of archaeological sites and museums.

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