what year did the mayflower land on plymouth bay
December 16, 1620
Landings at Provincetown and Plymouth
The "Mayflower" dropped anchor in Plymouth Harbor on December 16 
December 16 1620 December 21, 1620.
Plymouth Colony Plymouth Colony Plymouth Colony
Landings at Provincetown and Plymouth "Mayflower" voyage First winter
The "Mayflower" dropped anchor in Plymouth Harbor on December 16 and spent three days looking for a settlement site. The "Mayflower" departed Plymouth, England on September 6, 1620 with 102 passengers and about 30 crew members in the small, 106 foot-long ship. On December 21, 1620, the first landing party arrived at the site of Plymouth. 
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Plymouth Colony [SEP] Landings at Provincetown and Plymouth
A third expedition along Cape Cod left on December 6; it resulted in a skirmish with Indians known as the "First Encounter" near Eastham, Massachusetts. The colonists decided to look elsewhere, having failed to secure a proper site for their settlement, and fearing that they had angered the Indians by taking their corn and firing upon them. The "Mayflower" left Provincetown Harbor and set sail for Plymouth Harbor. The "Mayflower" dropped anchor in Plymouth Harbor on December 16 and spent three days looking for a settlement site. They rejected several sites, including one on Clark's Island and another at the mouth of the Jones River, in favor of the site of a recently abandoned settlement which had been occupied by the Patuxet tribe.