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The Sothic chronology of the Old Kingdom has not yet been securely established because of the small number of suitable dates from this period. An analysis of the Old Kingdom dates associated with seasonal events (wAgj feasts, expeditionary activity, the Nile cycles) reveals that seasonal activity was shifted about a month and a half earlier than would be expected given the actual seasons. This observation suggests that, in conventional chronological reconstructions, the age of the Old Kingdom is underestimated by about two centuries.