PLYMOUTH ROCK. Plymouth Rock is the stone upon which the Pilgrims were said to have stepped when the Mayflower arrived in Plymouth harbor on 21 December 1620. Identified in 1741 by Thomas Faunce, who was born in Plymouth, Massachusetts, in 1650, the massive rock was moved to the Town Square in 1774. Geologists classify it as an erratic glacial boulder of Dedham granite. Placed under an ornate portico in 1880, it was moved for the Tercentenary celebration in 1921 under an elaborate granite canopy on the hill overlooking Plymouth harbor. Although no evidence supports its legend, Plymouth Rock is a national icon that attracts countless tourists each year.
Seelye, John. Memory's Nation: The Place of Plymouth Rock. Chapel Hill: University of North Carolina Press, 1998.