The book Mourt's Relation: A Journal of the Pilgrims at Plymouth most likely contains

A journal written by people who were at Plymouth is a firsthand source, so it would most likely include the Pilgrims’ own accounts of arriving and landing there. “Mourt’s Relation” is a contemporary account of the early Plymouth settlement, rather than a later historical account of the voyage or the reasons the Pilgrims left Europe. The best choice is “firsthand accounts of the Pilgrims’ landing at Plymouth.”

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